Esperanto phonology

Not everyone agrees with Kalocsay & Waringhien that edzo and peco are a near rhyme, differing only in voicing, or on the status of /d͡z/ as a phoneme; Wennergren considers it to be a simple sequence of /d/ + /z/.

The letter ŭ is sometimes used as a consonant in onomatopoeia and unassimilated foreign names, in addition to the second element in diphthongs, which some argue is consonantal /w/ rather than vocalic /u̯/ (see below).

The primary difference is the absence of palatalization, although this was present in Proto-Esperanto (nacjes, now nacioj 'nations'; familje, now familio 'family') and arguably survives marginally in the affectionate suffixes -njo and -ĉjo, and in the interjection tju!

On the other hand, several distinctions between Esperanto consonants carry very light functional loads, though they are not in complementary distribution and therefore not allophones.

Later exceptions to these patterns, such as poŭpo ('poop deck'), ŭato ('watt'), East Asian proper names beginning with ⟨Ŭ⟩, and jida ('Yiddish'), are marginal.

The verb esti ('to be') behaves similarly, as can be seen by the occasional elision of the e in poetry or rapid speech: Mi ne 'stas ĉi tie!

[8] Within poetry, of course, the meter determines stress: Hó, mia kór', ne bátu máltrankvíle ('Oh my heart, do not beat uneasily').

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 ('short'), ek-kuŝi ('to flop down'), mis-skribi ('to mis-write'); in ethnonyms such as finno ('a Finn'), gallo ('a Gaul') (now more commonly gaŭlo); in proper names such as Ŝillero ('Schiller'), Buddo ('Buddha', now more commonly Budao); and in a handful of unstable borrowings such as matĉo ('a sports match').

In compounds of lexical words, Zamenhof separated identical consonants with an epenthetic vowel, as in vivovespero ('the evening of life'), never *vivvespero.

Sonorants and voiceless obstruents, on the other hand, are found in many of the numerals: cent ('hundred'), ok ('eight'), sep ('seven'), ses ('six'), kvin ('five'), kvar ('four'); also dum ('during'), eĉ ('even').

A very few words with final voiced obstruents do occur, such as sed ('but') and apud ('next to'), but in such cases there is no minimal-pair contrast with a voiceless counterpart (that is, there is no *set or *aput to cause confusion).

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.

In addition, initial ⟨pf⟩ occurs in German-derived pfenigo ('penny'), ⟨kŝ⟩ in Sanskrit kŝatrio ('kshatriya'), 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 ('a sphincter' which also has the coda ⟨nk⟩).

However, there is a strong tendency for more basic terms to avoid coda clusters, although cent ('hundred'), post ('after'), sankta ('holy'), and the prefix eks- ('ex-') (which can be used as an interjection: Eks la reĝo!

This root gave rise to two words in Esperanto, neither of which keep the full cluster: korpuso ('a military corps') (retaining the original Latin u), and korpo ('a biological body') (losing the s).

Many ordinary roots end in two or three consonants, such as cikl-o ('a bicycle'), ŝultr-o ('a shoulder'), pingl-o ('a needle'), tranĉ-i ('to cut').

(Note that the humorous jargon Esperant' does not follow this restriction, because it elides the grammatical suffix of all nouns no matter how awkward the result.)

This vowel is most commonly the nominal affix -o, regardless of number or case, as in kant-o-birdo ('a songbird') (the root kant-, 'to sing', is inherently a verb), but other part-of-speech endings may be used when -o- is judged to be grammatically inappropriate, as in mult-e-kosta ('expensive').

With only five oral and no nasal or long vowels, Esperanto allows a fair amount of allophonic variation, though the distinction between /e/ and /ei̯/, and arguably /o/ and /ou̯/, is phonemic.

Postalveolars ĉ, ĝ, ŝ, ĵ may be palato-alveolar (semi-palatalized) [t̠ʃ, d̠ʒ, ʃ, ʒ] as in English and French, or retroflex (non-palatalized) [t̠ʂ d̠ʐ ʂ ʐ] as in Polish, Russian, and Mandarin Chinese.

The grammatical reference Plena Manlibro de Esperanta Gramatiko considers the uvular trill [ʀ] to be perfectly acceptable.

Thus, the neologism senso ('sense', as in the five senses) may be pronounced the same as the fundamental word senco ('sense, meaning'), and the older term for the former, sentumo, may be preferable.

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' ('from the heart').

Zamenhof recognized place-assimilation of nasals before another consonant, such as n before a velar, as in banko [ˈbaŋko] ('bank') and sango [ˈsaŋɡo] ('blood'), or before palatal /j/, as in panjo [ˈpaɲjo] ('mommy') and sinjoro [siɲˈjoro] ('sir').

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 (Belo)Russian, rozkolora ('rose-colored', 'pink') would be pronounced the same as roskolora ('dew-colored'), and so the preferred form for the former is rozokolora.

Voicing assimilation of affricates and fricatives before nasals, as in taĉmento ('a detachment') and the suffix -ismo ('-ism'), is both more noticeable and easier for most speakers to avoid, so [ˈizmo] for -ismo is less tolerated than [apsoˈlute] for absolute.

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.

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, jida[note 9] ('Yiddish') was also sometimes criticized on phonotactical grounds, but was used by Zamenhof after its introduction in the Plena Vortaro as a replacement for novjuda and judgermana and is well established.