Esperanto phonology


Esperanto is a constructed international auxiliary language. The creator of Esperanto, L. L. Zamenhof, illustrated Esperanto pronunciation by comparing its sounds with their equivalents in several major European languages.
With over a century of use, Esperanto has developed a phonological norm, including accepted details of phonetics, phonotactics, and intonation, so that it is now possible to speak of proper Esperanto pronunciation and properly formed words independently of the languages originally used to describe Esperanto. This norm accepts only minor allophonic variation.
Before Esperanto phonotactics became fixed, foreign words were adopted with spellings that violated the apparent intentions of Zamenhof and the norms that would develop later, such as poŭpo, ŭato, and matĉo. Many of these coinages have proven to be unstable, and have either fallen out of use or been replaced with pronunciations more in keeping with the developing norms, such as pobo for poŭpo, vato for ŭato, and maĉo for matĉo. On the other hand, the word jida, which was also sometimes criticized on phonotactical grounds but had been used by Zamenhof, is well established.

Inventory

The original Esperanto lexicon contains 23 consonants, including 4 affricates and one,, which has become rare; and 11 vowels, 5 simple and 6 diphthongs. A few additional sounds in loan words, such as, are not stable.

Consonants

The uncommon affricate does not have a distinct letter in the orthography, but is written with the digraph, as in edzo. Not everyone agrees with Kalocsay & Waringhien that edzo and peco are a near rhyme, differing only in voicing, or on the status of as a phoneme; Wennergren considers it as a simple sequence of /d/ + /z/. The phoneme /x/ has been largely replaced with /k/ and is a marginal phoneme mostly found in loanwords and proper names such as ĉeĥo vs ĉeko. The voiced labio-velar approximant is sometimes found in onomatopoeia and in unassimilated foreign names, apart from the second element of diphthongs, which some argue is consonantal /w/ rather than vocalic .

Vowels

There are also six historically stable diphthongs:,,, and,. However, some authors such as John C. Wells regard them as vowel + consonant combinations, while Wennergren regards only the latter two as diphthongs.

Slavic origins

This inventory is rather similar to that of Polish, but is especially close to Belarusian, which was historically important to Zamenhof, the creator of Esperanto. The essential difference from Belarusian is the absence of palatalization, although this was present in Proto-Esperanto and arguably survives marginally in the affectionate suffixes -njo and -ĉjo, and in the interjection tju! Minor differences are that g is pronounced as a stop,, rather than as a fricative, ; a distinction between and ; and the absence of a diphthong oŭ, though that was added to Esperanto to a minor degree after its creation. Like Belarusian, is found in syllable onsets and in syllable codas; however, unlike Belarusian, does not become if forced into coda position through compounding, though Zamenhof avoided such situations by adding an epenthetic vowel: lavobaseno, not *lavbaseno or *laŭbaseno.

Orthography and pronunciation

The Esperanto alphabet is nearly phonemic. The letters, along with the IPA and nearest English equivalent of their principal allophone, are,

Minimal pairs

Esperanto has many minimal pairs between the voiced and voiceless plosives, /b d g/ and /p t k/; for example, ' "pay" vs. ' "pack", ' "bar" vs. ' "pair", ' "briefcase" vs. ' "group of ten".
On the other hand, the distinctions between several Esperanto consonants carry very light functional loads, though they are not in complementary distribution and therefore not allophones. The practical effect of this is that people who do not control these distinctions are still able to communicate without difficulty. These minor distinctions are ĵ vs. ĝ, contrasted in aĵo vs. aĝo ; k vs. ĥ vs. h, contrasted in koro vs. ĥoro vs. horo, and in the prefix ek- vs. eĥo ; dz vs. z, not contrasted in basic vocabulary; and c vs. ĉ, found in a few minimal pairs such as caro, ĉar ; ci, ĉi ; celo, ĉelo ; -eco, eĉ ; etc.
Belarusian seems to have also provided the model for Esperanto's diphthongs, as well as the complementary distribution of v, and ŭ, although this was modified slightly, with Belarusian oŭ corresponding to Esperanto ov, and ŭ being restricted to the sequences aŭ, eŭ in Esperanto. Although v and ŭ may both occur between vowels, as in naŭa and nava, the diphthongal distinction holds: vs.. The semivowel j likewise does not occur after the vowel i, but is also restricted from occurring before i in the same morpheme, whereas the Belarusian letter i represents. Later exceptions to these patterns, such as poŭpo, ŭato, East Asian proper names beginning with, and jida, are marginal.
The distinction between e and ej carries a light functional load, in the core vocabulary perhaps only distinctive before alveolar sonorants, such as kejlo, kelo ; mejlo, melo ; Rejno, reno. The recent borrowing gejo could contrast with the ambisexual prefix ge- if used in compounds with a following consonant, and also creating possible confusion between geja paro and gea paro, which are both pronounceable as. Eŭ is also uncommon, and very seldom contrastive: eŭro vs. ero.

Stress and prosody

Within a word, stress is on the penultimate syllable, with each vowel defining a syllabic nucleus: familio . An exception is when the final -o of a noun is elided, usually for poetic reasons, because this does not affect the placement of the stress: famili’.
On the rare occasions that stress needed to be specified, as in explanatory material or with proper names, Zamenhof used an acute accent. The most common such proper name is Zamenhof's own: Zámenhof. If the stress falls on the last syllable, it is common for an apostrophe to be used, as in poetic elision: Oĝalan’.
There is no set rule for which other syllables might receive stress in a polysyllabic word, or which monosyllabic words are stressed in a clause. Morphology, semantic load, and rhythm all play a role. By default, Esperanto is trochaic; stress tends to hit alternate syllables: Ésperánto. However, derivation tends to leave such "secondary" stress unchanged, at least for many speakers: Ésperantísto or Espérantísto Similarly, compound words generally retain their original stress. They never stress an epenthetic vowel: thus vórto-provízo, not *vortó-provízo.
Within a clause, rhythm also plays a role. However, referential words attract stress, whereas "connecting" words such as prepositions tend not to: dónu al mí or dónu al mi, not *dónu ál mi. In Ĉu vi vídas la húndon kiu kúras preter la dómo?, the function words do not take stress, not even two-syllable kiu or preter. The verb esti behaves similarly, as can be seen by the occasional elision of the e in poetry or rapid speech: Mi ne ’stas ĉi tie! Phonological words do not necessarily match orthographic words. Pronouns, prepositions, the article, and other monosyllabic function words are generally pronounced as a unit with the following word: mihávas, laknábo, delvórto, ĉetáblo. Exceptions include kaj 'and', which may be pronounced more distinctly when it has a larger scope than the following word or phrase.
Within poetry, of course, the meter determines stress: Hó, mia kór’, ne bátu máltrankvíle.
Emphasis and contrast may override normal stress. Pronouns frequently take stress because of this. In a simple question like Ĉu vi vídis?, the pronoun hardly needs to be said and is unstressed; compare Né, dónu al mí and. Within a word, a prefix that wasn't heard correctly may be stressed upon repetition: Né, ne tíen! Iru máldekstren, mi diris!. Because stress doesn't distinguish words in Esperanto, shifting it to an unexpected syllable calls attention to that syllable, but doesn't cause confusion as it might in English.
As in many languages, initialisms behave unusually. When grammatical, they may be unstressed: k.t.p. ; when used as proper names, they tend to be idiosyncratic: UEA or but rarely. This seems to be a way of indicating that the term is not a normal word. However, full acronyms tend to have regular stress: Tejo.
Lexical tone is not phonemic. Nor is clausal intonation, as question particles and changes in word order serve many of the functions that intonation performs in English.

Phonotactics

A syllable in Esperanto is generally of the form V. That is, it may have an onset, of up to three consonants; must have a nucleus of a single vowel or diphthong, and may have a coda of zero to one consonants.
Any consonant may occur initially, with the exception of j before i.
Any consonant except h may close a syllable, though coda ĝ and ĵ are rare in monomorphemes. Within a morpheme, there may be a maximum of four sequential consonants, as for example in instruas, dekstren. Long clusters generally include a sibilant such as s or one of the liquids l or r.
Geminate consonants generally only occur in polymorphemic words, such as mal-longa, ek-kuŝi, mis-skribi ; in ethnonyms such as finno, gallo ; in proper names such as Ŝillero, Buddo ; and in a handful of unstable borrowings such as matĉo. In compounds of lexical words, Zamenhof separated identical consonants with an epenthetic vowel, as in vivovespero, never *vivvespero.
Word-final consonants occur, though final voiced obstruents are generally rejected. For example, Latin ad became Esperanto al, and Polish od morphed into Esperanto ol. Sonorants and voiceless obstruents, on the other hand, are found in many of the numerals: cent, ok, sep, ses, kvin, kvar ; also dum, eĉ. Even the poetic elision of final -o is rarely seen if it would leave a final voiced obstruent. A very few words with final voiced obstruents do occur, such as sed and apud, but in such cases there is no minimal-pair contrast with a voiceless counterpart. This is because many people, including the Slavs and Germans, do not contrast voicing in final obstruents. For similar reasons, sequences of obstruents with mixed voicing are not found in Zamenhofian compounds, apart from numerals and grammatical forms, thus longatempe 'for a long time', not *longtempe.
Syllabic consonants occur only as interjections and onomatopoeia: fr!, sss!, ŝŝ!, hm!.
All triconsonantal onsets begin with a sibilant, s or ŝ. Disregarding proper names, such as Vladimiro, the following initial consonant clusters occur:
And more marginally,
The affectionate suffixes -ĉj- and -nj-, which retain remnants of the Slavic palatalized consonants, may very occasionally be used as words in their own right, as in mia ĉjanja popolo, in which case they may be word initial and not just syllable initial.
Although it does not occur initially, the sequence is pronounced as an affricate, as in edzo with an open first syllable , not as.
In addition, initial occurs in German-derived pfenigo, in Sanskrit kŝatrio, and several additional uncommon initial clusters occur in technical words of Greek origin, such as mn-, pn-, ks-, ps-, sf-, ft-, kt-, pt-, bd-, such as sfinktero. Quite a few more clusters turn up in sufficiently obscure words, such as in tlaspo "Thlaspi", and Aztec deities such as Tlaloko.
As this might suggest, greater phonotactic diversity and complexity is tolerated in learnèd than in quotidian words, almost as if "difficult" phonotactics were an iconic indication of "difficult" vocabulary. Diconsonantal codas, for example, generally only occur in technical terms, proper names, and in geographical and ethnic terms: konjunkcio, arkta, istmo.
However, there is a strong tendency for more basic terms to avoid such clusters, although cent, post, sankta, and the prefix eks- are exceptions. Even when coda clusters occur in the source languages, they are often eliminated in Esperanto. For instance, many European languages have words relating to "body" with a root of korps-. This root gave rise to two words in Esperanto, neither of which keep the full cluster: korpuso , and korpo .
Many ordinary roots end in two or three consonants, such as cikl-o, ŝultr-o, pingl-o, tranĉ-i. However, these roots do not normally entail coda clusters except when followed by another consonant in compounds, or with poetic elision of the final -o. Even then, only sequences with decreasing sonority are possible, so although poetic tranĉ’ occurs, *cikl’, *ŝultr’, and *pingl’ do not.
Within compounds, an epenthetic vowel is added to break up what would otherwise be unacceptable clusters of consonants. This vowel is most commonly the nominal affix -o, regardless of number or case, as in kant-o-birdo , but other part-of-speech endings may be used when -o- is judged to be grammatically inappropriate, as in mult-e-kosta. There is a great deal of personal variation as to when an epenthetic vowel is used.

Allophonic variation

With only five oral and no nasal or long vowels, Esperanto allows a fair amount of allophonic variation, though the distinction between and, and arguably and, is phonemic. The may be a labiodental fricative or a labiodental approximant, again in free variation, or, especially in the sequences kv and gv, but with considered normative. Alveolar consonants t, d, n, l are acceptably either apical or laminal. Postalveolars ĉ, ĝ, ŝ, ĵ may be palato-alveolar as in English and French, or retroflex as in Polish, Russian, and Mandarin Chinese. H and ĥ may be voiced, especially between vowels. H

Rhotics

The consonant r can be realised in many ways, as it was defined differently in each language version of the Fundamento de Esperanto:
The most common realisation depends on the region and native language of the Esperanto speaker. For example, a very common realisation in English speaking countries is the alveolar flap. Worldwide, the most common realisation is probably the alveolar trill, which makes some people think it is the most desirable pronunciation. However, it is a common misconception to believe that the alveolar trill is the only correct form. The grammar reference Plena Manlibro de Esperanta Gramatiko considers the velar form to be totally good if it is trilled, and considers the other realisations acceptable. In practice, the different forms are well understood and accepted by experienced Esperanto speakers.

Vowel length and quality

Vowel length is not phonemic in Esperanto. Vowels tend to be long in open stressed syllables and short otherwise. Adjacent stressed syllables are not allowed in compound words, and when stress disappears in such situations, it may leave behind a residue of vowel length. Vowel length is sometimes presented as an argument for the phonemic status of the affricates, because vowels tend to be short before most consonant clusters, but long before /ĉ/, /ĝ/, /c/, and /dz/, though again this varies by speaker, which some speakers pronouncing a short vowel before /ĝ/, /c/, /dz/ and a long vowel only before /ĉ/.
Vowel quality has never been an issue for /a/, /i/ and /u/, but has been much discussed for /e/ and /o/. Zamenhof recommended pronouncing the vowels /e/ and /o/ as mid at all times. Kalocsay and Waringhien gave more complicated recommendations. For example, they recommended pronouncing stressed /e/, /o/ as short open-mid in closed syllables and long close-mid in open syllables. However, this is widely considered unduly elaborate, and Zamenhof's recommendation of using mid qualities is considered the norm. For many speakers, however, the pronunciation of /e/ and /o/ reflects the details of their native language.

Epenthesis

Zamenhof noted that epenthetic glides may be inserted between dissimilar vowels, especially after high vowels as in for mia, for mielo and for plua. This is quite common, and there is no possibility of confusion, because /ij/ and /uŭ/ do not occur in Esperanto. However, Zamenhof stated that in "severely regular" speech such epenthesis would not occur.
Epenthetic glottal stops in vowel sequences such as boao are non-phonemic detail, allowed for the comfort of the speaker. Glottal stop is especially common in sequences of identical vowels, such as heroo , and praavo . Other speakers, however, mark the hiatus by a change of intonation, such as by raising the pitch of the stressed vowel: heróò, pràávo.
As in many languages, fricatives may become affricates after a nasal, via an epenthetic stop. Thus the neologism senso may be pronounced the same as the fundamental word senco, and the older term for the former, sentumo, may be preferable.

Poetic elision

Vowel elision is allowed with the grammatical suffix -o of singular nominative nouns, and the a of the article la, though this rarely occurs outside of poetry: de l’ kor’.
Normally semivowels are restricted to offglides in diphthongs. However, poetic meter may force the reduction of unstressed and to semivowels before a stressed vowel: kormilionoj ; buduaro.

Assimilation

Zamenhof recognized place-assimilation of nasals before another consonant, such as n before a velar, as in banko and sango , or before palatal, as in panjo and sinjoro . However, he stated that "severely regular" speech would not have such variation from his ideal of 'one letter, one sound'. Nonetheless, although the desirability of such allophony may be debated, the question almost never arises as to whether the m in emfazi should remain bilabial or should assimilate to labiodental f, because this assimilation is nearly universal in human language. Indeed, where the orthography allows, we see that assimilation can occur.
In addition, speakers of many languages have voicing assimilation, usually regressive, when two obstruents occur next to each other. Zamenhof did not mention this directly, but did indicate it indirectly, in that he didn't create compound words with adjacent obstruents that have mixed voicing. For example, by the phonotactics of both of Zamenhof's mother tongues, Yiddish and Russian, rozkolora would be pronounced the same as roskolora, and so the preferred form for the former is rozokolora.
Indeed, Kalocsay & Waringhien state that when voiced and voiceless consonants are adjacent, the assimilation of one of them is "inevitable". Thus one pronounces okdek as 'ogdek', ekzisti as 'egzisti' and ekzemple as 'egzemple', subteni as 'supteni', longtempe as 'lonktempe', glavsonoro as 'glafsonoro'. Such assimilation likewise occurs in words that maintain Latinate orthography, such as absolute as 'apsolute' and obtuza as 'optuza', despite the potentially contrastive sequences in words such as apsido and optiko. Instead, the debate centers on the non-Latinate orthographic sequence kz, frequently found in Latinate words like ekzemple and ekzisti above. It is often claimed that kz is properly pronounced exactly as written, with mixed voicing,, despite the fact that assimilation occurs in Russian, English, French, and many other languages. These two opinions are called ekzismo and egzismo in Esperanto. In practice, most Esperanto speakers assimilate both kz to and nk to when speaking fluently.
In compound lexical words, Zamenhof himself inserted an epenthetic vowel between obstruents with different voicing, as in rozokolora above, never *rozkolora, and longatempe, never *longtempe as with some later writers; mixed voicing only occurred with grammatical words, for example with numbers and with prepositions used as prefixes, as in okdek and subteni above. V is also never found before a consonant in Zamenhof's writing, because that would force it to contrast with ŭ.
Similarly, mixed sibilant sequences, as in the polymorphemic disĵeti, tend to assimilate in rapid speech, sometimes completely.
Like the generally ignored regressive devoicing in words such as absurda, progressive devoicing tends to go unnoticed within obstruent–sonorant clusters, as in plua and knabo . Partial to full devoicing of the sonorant is probably the norm for most speakers.
Voicing assimilation of affricates and fricatives before nasals, as in taĉmento and the suffix -ismo, is both more noticeable and easier for most speakers to avoid, so for -ismo is less tolerated than for absolute.

Loss of phonemic ''ĥ''

The sound of, was always somewhat marginal in Esperanto, and there has been a strong move to merge it into, starting with suggestions from Zamenhof himself. Dictionaries generally cross-reference and, but the sequence was replaced by so completely by the early 20th century that few dictionaries even list as an option. Other words, such as ĥemio and monaĥo, still vary but are more commonly found with . In a few cases, such as with words of Russian origin, may instead be replaced by. This merger has had only a few complications. Zamenhof gave ĥoro the alternative form koruso, because both koro and horo were taken. The two words still almost universally seen with are eĥo and ĉeĥo. Ek- and ĉeko already exist, though ekoo for eĥo is occasionally seen.

Proper names and borrowings

A common source of allophonic variation is borrowed words, especially proper names, when non-Esperantized remnants of the source-language orthography remain, or when novel sequences are created in order to avoid duplicating existing roots. For example, it is doubtful that many people fully pronounce the g in Vaŝingtono as either or, or pronounce the in Budho. Such situations are unstable, and in many cases dictionaries recognize that certain spellings are inadvisable. For example, the physical unit "Watt" was first borrowed as ŭato, to distinguish it from vato, and this is the only form found in dictionaries in 1930. However, initial violates Esperanto phonotactics, and by 1970 there was an alternative spelling, vatto. This was also unsatisfactory, however, because of the geminate, and by 2000 the effort had been given up, with now the advised spelling for both "Watt" and "cotton-wool". Some recent dictionaries no longer even list initial in their index. Likewise, several dictionaries now list a newer spelling for Washington.