Chapter Eleven
Word Formation in Esperanto

Copyight © 2002 Sylvan Zaft. This is the 11th chapter of Esperanto: A Language for the Global Village.  You may make electronic copies and paper copies for your personal use, and you may freely distribute verbatim copies which include this notice provided that you do not charge for these copies.   You may not post this material to any site.   You are invited to insert links to any of these sites.   For any other use, including publication, you must first get my permission.   I welcome any suggestions about how to improve this work.   My address is sylvanz@me.com.

The Invariable Morphemes of Esperanto

Languages combine morphemes to form words.  Morphemes are little words and parts of words that have a meaning by themselves.  In English, the word dog has just one morpheme, but dogs has two, dog and s.  The morpheme –s means “more than one.” The word learned contains the morpheme –ed which means “took place in the past.”

In many languages, including English, morphemes change inside themselves.  For instance, mouse changes to mice to indicate that there is more than one.  Give changes to gave to show that the action took place in the past. 

Every time an English morpheme changes inside itself, the foreign student has another new learning burden to deal with.  Since hundreds of English morphemes change inside themselves, this adds up to a significant learning burden.

Esperanto morphemes do not change inside themselves.  Once students learn an Esperanto morpheme, they do not have to worry about having to memorize variations of that morpheme.

Speakers and writers of Esperanto are free to combine the unchanging morphemes of the language to create new, instantly recognizable words. 

Kur is a morpheme that means “run.” (Kur by itself is not normally used as a word.) Adding the noun ending –o gives kuro which means “running.” Adding different verbal endings gives these verb forms:

         Add –i, and you form the infinitive kuri (to run.)

         Add –is, and you form the past tense kuris (ran.)

         Add –as and you form the present tense kuras (run, runs.)

         Add –os, and you form the future tense kuros (will run, is going to run.)

         Add –us and you form the conditional kurus (would run.)

         Add –u and you form the imperative kuru (Run!)

These endings may be added to any morpheme to create a verb, as long as the resulting verb makes sense.

 That is all that there is to it. 

The Changing Morphemes of English

The corresponding English morpheme run does change inside itself.  Run becomes ran to form the past tense.  In the gerund run becomes runn, as part of running.

Here are eight English words that change inside themselves:

1 tooth teeth    
2 think thought    
3 meet met    
4 forget forgettable    
5 army armies    
6 man men    
7 sink sank sunk  
8 lie lay lain lying

Here are the corresponding Esperanto forms for the above words.  The unchanging root is in bold print.  You cannot put the unchanging root in the English forms above in bold print because there are no unchanging roots.

1 dento dentoj    
2 pensas pensis    
3 renkontas renkontis    
4 forgesas forgesis    
5 armeo armeoj  


6 viro viroj    
7 sinkas sinkis sinkinta  
8 kuŝas kuŝis kuŝinta kuŝanta

English is rich in compound words, words formed by putting morphemes together.  Some examples are “pussyfoot”, “pushover”, “muckraker”, “ferryman” and “crankshaft.” Speakers of Esperanto are free to put together not only short words but any morphemes whatsoever in order to form new words.  The only limitation is that they must make sense.  It has been said that word formation in Esperanto is governed by logic.  Word formation in English is governed by an enormous number of arbitrary rules.

The Freedom to Create New Words by Combining Morphemes

Someone once asked, “How many words are there in Esperanto?”

The answer is “An indefinite number.” Because speakers of Esperanto may combine the elements of the language in any way that makes sense, they can freely create new words out of existing components and be understood by people who never heard or saw those new words before.  Someone who has mastered just a thousand basic morphemes of Esperanto can create tens of thousands of words from them. 

Speakers of languages such as English and French do not enjoy this enormous degree of freedom.  Consider these English words:






Suppose some newcomers to Esperanto wanted to express these ideas.  Suppose these students knew these concepts and had words for them in their native language and suppose that they knew the Esperanto for these morphemes: not, regular, God, believe, natural, sense and possible.  The students could easily form these Esperanto counterparts and be instantly understood:






Many Esperantists use ateisto for “atheist.”  However, the word that the student constructed, which literally means not-god-believer, is a perfectly good Esperanto word and one which everyone who knows some basic Esperanto will immediately understand.

Foreign students of English lack this freedom.  Suppose that a particular foreign student knows the English words: regular, God, believe, natural, sense, possible.  Suppose further that this student has learned a number of different English prefixes which are used to express the idea of “not.”  These prefixes include un as in “untrue”, ir as in “irresistible”, im as in “immaterial” and in as in inhumane.  Suppose that this student freely combines morphemes, using their correct meanings, and comes up with these words:






Even though these words are constructed logically out of English morphemes, they are simply not permitted according to the rules of the language.  Foreign students have to laboriously learn one at a time thousands of different possible combinations which are permitted, and they must be very careful not to use those which are not permitted for fear of risking censure, puzzled looks or even laughter.  Since many perfectly normal people do not like to be laughed at, the threat of laughter can act as a powerful inhibiting factor when it comes to practicing a foreign language in a real-life situation.

Months of Hard Work

Complicated national languages such as English with their tens of thousands of arbitrary rules are simply not suitable for use as a universal auxiliary international language because, except for the linguistically gifted, such languages cannot be learned in a few months of hard work.  Each of these languages has its own difficulties, but all of them are so difficult that they require a great many thousands of hours to master to the point where they can be spoken and written comfortably and correctly, except for a very, very few linguistic geniuses.

Those people who really become comfortable in a second national language normally do so after spending a lot of time in a country where that language is spoken.  What often accompanies this is that they become rusty in their native language.

For example, I once met a woman who spent her first nine years in Belgium, where she was born, using French as her native language, and then spent three years in Quebec where she continued to use French.  The family then moved to the United States.  Ever since she has used English.  She speaks without a foreign accent.  However, when she sees a French film she has to use the subtitles.  When she and her mother speak on the telephone they speak in English, not French.

I met an American teen-ager who had spent her junior year in Austria.  She had become fluent in German which she used every day.  But she found on returning to the United States that she had to very frequently search for words.  She spoke English haltingly.  After three weeks she had regained much of her English and I am certain that after another three weeks she must have regained full possession of her English.  However, she might have lost some of her fluency in German.

I know a professor who as a student spent a year in Austria.  He became fluent in German.  Many years later he was teaching physics in French in an African country where French was the national language.  German-speaking visitors arrived.  He had looked forward to speaking to them in German.  He found he could not converse with them in German.

For a great many people maintaining a national language, even one’s native language, means constant practice because such languages are very complex.  Fluency, once lost, can be regained, but it takes some time.  Fluency in Esperanto once lst can also be regained – in a small fraction of the time, as the experience of the woman from Yugoslavia shows.

As a national language, English works magnificently.  People who grow up with the language and use it throughout their lives master its intricacies and display that mastery without even having to think about it.  On the other hand, for the person who learns English for occasional use as an auxiliary international language, the complexities of English present an enormous superfluous extra learning load.  The other great unplanned languages also work wonderfully as national languages, but they are also incredibly difficult to learn as a second language, each for its own reasons.

English is used as an international language today in a great many fields.  When native speakers of English speak their language as an international language they do beautifully.  People from some countries who have studied English for eight or twelve years may also do very well, especially if their native language is akin to English.  However, in many cases, as has been said, the international language used in discussions in international meetings is broken English.

The freedom to put morphemes together to create new, instantly recognizable words is one of the reasons why Esperanto is learned by many individuals in a few months of diligent, serious study.

Before we delve more deeply into this powerful feature of Esperanto, it is important to emphasize the uniqueness of each language’s way of communicating ideas.

Languages are not Codes for Each Other

There are many individuals who suffer from the misconception that other languages should be word-for-word equivalents for their own.  This misconception is based on the unstated assumption that the words and expressions of a foreign language are or ought to be one-for-one equivalents for the words and expressions of their own language.  Since the patterns of their own language are so natural to them, it seems reasonable to assume that these familiar patterns are natural to languages generally.

This is true for secret codes.  Those who write in a certain kind of code first think out their message in their own language and then look up the equivalent for each word in a code book.  Then they write down those equivalents.  If the code is a numerical one they might come up with something like this: 0973 9145 3329 6728 6651 7159 4029 1182.

The recipient of the message in turn consults a code book and turns the message back into regular words.

The problem is that anyone who tries that trick with real languages will come up with laughter-provoking sentences.

The humorist Mark Twain made use of this.  He translated an item from a Mannheim Germany newspaper word-for-word into English.  This is the kind of English that he came up with:

In the daybeforeyesterdayshortlyaftereleveno’clock Night, the inthistownstandingtavern called ‘The Wagoner’ was downburnt.

In German it is natural to use long compound words that would look very strange in English, and Twain as a humorist exploited this for laughs.

Humorists could have similar fun with Kivunjo, the African language referred to earlier, where one complex word may do the work of a six-word English sentence; or Japanese, where the verb must always come at the end of the sentence, or any other foreign language.

We could try Mark Twain’s trick with another language.  Here is a passage from the famous French novel, The Three Musketeers by Alexandre Dumas:

D’Artagnan la releva en lui passant le bras autour de la taille; mais comme il sentait à son poids qu’elle etait sur le point de se trouver mal, il s’empressa de la rassurer par des protestations de dévouement.

Here’s a Mark-Twainish word-for-word rendering of this passage into English:

D’Artagnan her reraised in her passing the arm around of the waist; but as he felt to her weight that she was on the point of herself tofind bad, he himself hastened of her toreassure by ofthe protestations of devotion.

A pattern of words that is perfectly natural in French, which was used by one of the most successful French authors, is simply ridiculous in English.

Of course a French humorist or a German humorist or a Kivunjo humorist or a Japanese humorist could have the same kind of fun by translating word-for-word some English sentence into their language.  The results would be just as laughter-provoking to French or German or Kivunjo or Japanese ears.

Unlike the case with the secret code, languages are not word-for-word equivalents for each other.  Each language must be taken on its own terms.  A person’s mother tongue, whatever it might be, is not the one true paradigm for understanding the basic nature of language.  No matter how dominant a language might be in one country or even in many fields world-wide, it is just one form of language out of the many thousands that have developed.

Languages become dominant in the world not because they are learned easily but because of the dominance of the nations whose national tongues they are.

Like other languages, Esperanto has its own ways of expressing ideas.  Esperanto sentences, like French or German sentences, may sound odd when translated word-for-word into English.  In addition, when we analyze Esperanto words in terms of English morphemes, the results may seem odd to English ears.  This does not mean that there is anything wrong with Esperanto or with English.  Languages just work differently. 

A Sentence by a Nobel-Prize Winning Esperantist

With this in mind, let us see how the system of combining morphemes to create new words works in practice.  Let us consider a sentence taken from an interview that was held in Esperanto.  In 1994 Professor Reinhard Selten of Germany became the first Esperantist in many years to win a Nobel Prize when he shared the Nobel Memorial Prize in Economics.  Here he explains what his specialty, game theory, is:

La ludo-teorio estas matekmatika teorio pri konflikto kaj kunlaborado, en kiuj oni povas kunagadi, aŭ kontraŭi unu la alian, aŭ samtempe, ambaŭ.

Game theory is a mathematical theory about conflict and collaboration, in which you can act together or act against one another, or, at the same time, both.

Now here is each Esperanto word followed by its literal English meaning:

la = the
ludo-teorio = game-theory
estas = is
matematika = mathematical
teorio = theory
pri = about
konflikto = conflict
kaj = and
kunlaborado = with-working
en = in
kiuj = which (plural)
oni = one
povas = can
kunagadi = to-with-act
= or
kontraŭi = to-against
unu = one
alian = another (direct object)
samtempe = same-time-ly
ambaŭ = both


Putting these words together in the manner of Mark Twain we come up with:

The game-theory is mathematical theory about conflict and withworking, in which one can towithact or toagainst one another, or sametimely both. 

Analyzing this sentence can show us how Esperanto and English behave differently from each other.

One difference between the two languages is in the use of articles.  In English we say “game theory” but in Esperanto Selten said “la ludo-teorio” which is like saying “the game theory.” On the other hand in English we speak of “a mathematical theory.” Like Russian, Esperanto has no equivalent for a or an.  As has already been indicated, one of the purposes of a is to indicate that a noun is coming up, and the noun-ending –o does that little job in Esperanto.

Now let us look at some specific words that Professor Selten used in this sentence which he spoke answering a question from the interviewer. 


Kunlaborado is made up of four morphemes, kun, labor, ad and o

When foreign students of English learn the English words “houseboat” and “boathouse” they learn to read them from right to left.  Thus a “houseboat” is a boat that serves as a house, and a “boathouse” is a house for boats.

Let us read kunlaboro the same way.  Here are the four morphemes, right to left:

       The ending –o makes the word a noun.

       The morpheme –ad indicates duration, that a process goes on for a while.  (English does this with verbs by using a form like “she was eating” instead of simply saying “she ate.” Esperantists can add –ad to a verb to get this effect.  Esperantists can also add –ad to nouns and adverbs and adjectives to get this effect.)

       The morpheme labor means “work.”

       The morpheme kun means “with.”

We come up with this: a noun that means “work with.” (Sometimes morphemes like the English a or an or the Esperanto ad are not translated.) Kunlaborado is similar in structure to the English word “collaboration.” According to Webster’s New World Dictionary, collaboration comes from the Latin word collaboratus which is derived from two Latin words com (simplified here to co) which means “with” and labor which means “work.” The final morpheme ation marks the word as a noun.

The difference here is that Esperanto speakers have the right to combine kun and labor and o simply because it makes sense.  Students of English may not do this with with and work and come up with withwork or withworkation even though it would make sense.  Instead they are required to use “working together” or “collaboration.” As has already been stressed, foreign students of English have to learn which thousands of combinations of morphemes are permissible and which thousands or tens or thousands or hundreds of thousands are not.  In Esperanto, as long as they make sense, this kind of combination of morphemes is always permitted.


Kontraŭi is made up of the adverbial root kontraŭ which means “against” and the ending –i, which marks the infinitive of a verb.  Kontraŭi literally means “to against.”

The students of Esperanto are free to turn any word into a noun, an adjective, an adverb or a verb by simply using the appropriate ending for that kind of word. 

Foreign students of English cannot say “to against” even though this might make sense.  They must remember to say “to be against” or else use an entirely different word “to oppose”.

The student of Esperanto is also free to say esti kontraŭ (to be against) simply because that too makes sense.


Kunagadi is made up out of four morphemes, three of which we already know.

The new morpheme, ag, means “act” in the sense of doing something.

Reading kunagadi from right to left, we see that it means “to continuously act with” or, as we would say in good English, “to continuously act together.”

In this case a single Esperanto word is the equivalent of a four-word English phrase.


Samtempe has three morphemes.  Sam means “same.” Temp means “time.” The ending –e, like the English ending –ly, marks a word as an adverb.  We may read samtempe to mean “sametimely.”

Foreign students of English may not use “sametimely” but may choose between the prepositional phrase “at the same time” or a word of Latin origin, “simultaneously.”

The Esperanto student can also say “at the same time” je la sama tempo because it too makes sense.

Imagine if foreign students had these kinds of possibilities available to them in English.  It would make English much easier for them.  Of course, they do not have these possibilities.  This is just another reason why English is so terribly difficult for them to master.

The Creative Pleasure of Combining Morphemes

Let us see how Esperantists use this feature of freely combining morphemes to make their language interesting and colorful.  Here are some examples taken from one of Claude Piron’s detective novels which he published under the pseudonym of Johan Valano:

1.  altranguloj

alt = high
rang = rank
ul = person, guy
o = [noun marker]
j = [plural marker]

So: altranguloj = “big shots” or “higher-ups.”


facil = easy
anim = soul
e = [adverb marker]


So: facilanime = “with an easy soul” or, as the English idiom as it, “with an easy heart.”

3.  kunparolantino

kun = with
parol = speak
ant = one who is
in = female
o = [noun marker]

So: kunparolantino = “a female who is taking part in a conversation or dialogue.”

Because Esperantists can freely create new words that are instantly understood, the language is very rich in synonyms.  Here is a group of synonyms, all of which refer to some kind of comrade or companion:

1.  kamarado

kamarad = comrade, pal
o = [noun marker]

Kamarado means “comrade”

2.  kunulo

kun = with
ul = person, guy
o = [noun marker]

Kunulo means “companion”, someone who is with somebody.

3.  kuniranto  

kun = with
ir = go
ant = one who is
o = [noun marker]

Kuniranto means a special kind of companion, someone who is going along with someone else.

4.  kunvojaĝanto      

kun = with
vojaĝ = vojage, trip
ant = one who is
o = [noun marker]

Kunvojaĝanto is someone who is taking a trip with someone else.

5.  vojkunulo

voj = way, path
kun = with
ul = person, guy
o = [noun marker]

Vojkunulo is someone who is going along the same path or road or way with someone else.

6.  samsortulo

sam = same
sort = fate
ul = person, guy
o = [noun marker]

Samsortulo is someone who shares the same fate as someone else.

Such compound words are instantly understandable because they are made up of very common morphemes.  Of course, no one is required to use a whole lot of synonyms, but if the need is felt, perhaps for literary purposes, to select among possible synonyms to convey fine grades of meaning, the Esperanto system of freely combining morphemes makes this possible without requiring the student to memorize enormous numbers of individual words.

The words just given form part of a list of ten given by Claude Piron.  However, as Piron points out, many more possibilities exist.

Here is one that comes to mind.

Kvankam Hitler kaj Stalin estis malamikoj, ili estis samfarantoj.

Although Hitler and Stalin were enemies, they were “samfarantoj.”

Now how can we translate this word, samfarantoj, into English? The components are easy enough to understand:

sam = same
far = do
ant = one who is
o = [noun marker
j = [plural marker]

The translation that comes to my mind is “people who do the same kinds of things.” In English the sentence becomes:

Although Hitler and Stalin were enemies, they were people who did the same kinds of things.

There are other ways of expressing this in English.  However, none of them that I can think of are as concise as samfarantoj.

When people speak and write their native language they quite naturally create new sentences which never existed before.  Most of the words that Esperantists use are words that they have learned, but at times they spontaneously create words that are new to them.

Here is an example:

In Lancaster, Pennsylvania we were finishing up a weekend conference with a little picnic in a park.  Little by little people said good-by and left.  At one point someone asked where the person who had organized the conference was.  I responded, “Li altrajnigis la aliajn.” Three of these words are very easy to translate into English:

li = he
la = the
aliajn = others (direct object)

The fourth word, altrajnigis , is more complex.  It means, “took to the train.” Here are its morphemes:

al = to
trajn = train
ig = cause
is = [past tensemarker] in the past

In short, the sentence means “he caused to the train the others” or, in good English, “he took the others to the train.”

Of course the English sentence “he took the others to the train” works perfectly, and I could have made up an Esperanto sentence with the equivalent words: “Li alportis la aliajn al la trajno.”

Because of the flexible nature of Esperanto I could have expressed this idea in many other ways as well.  Here is one more:

“Li altrajne ŝoforis ilin” means “He totrainly drove them.”

However, “Li altrajnigis la aliajn” just came out of my mouth, just as the sentences that you speak in an ordinary conversation just come out of your mouth.  Esperanto is a very flexible language with many different ways of expressing a thought so that speakers or writers may select or devise the ones that works best according to their taste.  It is this multitude of possibilities that makes it possible for students to be very expressive in Esperanto even though they may know only about a thousand morphemes.

Let me conclude by indicating some words I recently used in a little essay on the “soc.culture.esperanto” newsgroup of the Internet:

1.  retsendas

ret = network
send = send
as = [present tense]

Retsendas means “send by means of the internet.”

2.  retsendaĵo

ret = network
send = send
= specific thing, concrete object
o = [noun marker]

Retsendaĵo means “something sent by means of the internet” (a posting on the internet.)

3.  enretigi

en = in
ret = network
ig = cause
i = [infinitive]

Enretigi means “to put in the internet.” (In English we would usually say “to put on the internet.” Different languages use prepositions differently.  This feature of languages is gone into in a later chapter.)

4.  nurangleleganto

nur = only
angl = English
e = [adverb marker]
leg = read
ant = one who
o = [noun marker]

Nurangleleganto means “someone who reads only English.”

5.  informpetanto

inform = only
pet = English
ant = one who
o = [noun marker]

Informpetanto means “someone who requests information.”

6.  mondskalas

mond = world
skal = scale
as = [present tense]

Mondskalas means “operates on a world-wide scale.”

I did not remember having seen any of these words before.  (Of course they all might have been used before.) The point is that because I knew their component morphemes, I was able to spontaneously come up with these words.  Because of the rules of word-formation in Esperanto I did not have to worry about checking through dictionaries to see if the words were “good Esperanto” or not.  As a speaker of a language which was specifically designed to be easily learned for international use, I have a right to make up such words.

The situation is quite different in English.  While writing an earlier part of this chapter the English word illogicity came into my mind.  After writing it down I wondered if it was a valid English word.  I knew my readers would understand it, but I also knew that I had no right to use it unless it was an established English word. 

First I checked in an excellent college dictionary.  It was not there. 

Then I looked in the Oxford English Dictionary.  This greatest of all English dictionaries told me that the Daily Telegraph had used illogicity in 1886.  It was an established English word.  I had the right to use it.

The same natural process which all competent English speakers use when they speak their language is used by Esperantists when they speak theirs.  The difference is that the English speaker only has the right to use this process freely in creating sentences.  The Esperantist also has the right to use this process in creating new words.

In the last chapter we learned that native speakers of English enjoy a vast array of idiomatic expressions with which they can express their thoughts. 

Those foreign students of English who have only several hundreds of hours to devote to the study of the language can only make use of a limited number of these expression.  For this reason and because of the other complexities of the language, most foreign students can only hope to learn English to a rudimentary degree. 

With a similar investment of time students of Esperanto can become sophisticated users of the language because they enjoy the freedom to create new, colorful, apt words out of whatever morphemes, out of whatever “little words”, they choose to use.

Such students discover that Esperanto is a very expressive language indeed.


Chapter Twelve    The Pattern-Making Power of the Human Mind

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