Sound values

The letters have approximately the sound values of the IPA, with the exception of c [t͡s] and the letters with diacritics: ĉ [t͡ʃ], ĝ [d͡ʒ], ĥ [x], ĵ [ʒ], ŝ [ʃ], ŭ [u̯]. J transcribes two allophonic sounds, consonantal [j] (the English y sound, as in you) and vocalic [i̯].^[1]

There is a nearly one-to-one correspondence of letter to sound. For those who consider /d͜z/ to be a phoneme, Esperanto contains one consonantal digraph, ⟨dz⟩.^[3] Beside the dual use of ⟨j⟩, allophony is found in place assimilation of /m/ and /n/, the latter of which for example is frequently pronounced [ŋ] before g and k.

Phonemic change is perhaps limited to voicing assimilation, as in the sequence kz of ekzemplo, ('(an) example') which is frequently pronounced /ɡz/. In Zamenhof's writing, obstruents with different voicing do not meet in compound words, but rather are separated by an epenthetic vowel such as o, to avoid this effect.

Non-Esperantized names are given an Esperanto approximation of their original pronunciation, at least by speakers without command of the original language. Hard ⟨c⟩ is read as k, ⟨qu⟩ as kv, ⟨w⟩ as v, ⟨x⟩ as ks, and ⟨y⟩ as j if a consonant, or as i if a vowel. The English digraph ⟨th⟩ is read as t. When there is no close equivalent, the difficult sounds may be given the Esperanto values of the letters in the orthography or roman transcription, accommodating the constraints of Esperanto phonology. So, for example, Winchester (the English city) is pronounced (and may be spelled) Vinĉester /vint͜ʃester/, as Esperanto ŭ does not occur at the beginning of ordinary words.^[4] Changzhou generally becomes Ĉanĝo /t͜ʃand͜ʒo/, as Esperanto has no ng or ou sound. There are no strict rules, however; speakers may try for greater fidelity, for example by pronouncing the g and u in Changzhou: Ĉangĝoŭ /t͜ʃaŋɡd͜ʒou̯/ (despite there being no g sound in the Chinese pronunciation). The original stress may be kept, if it is known.

Origin

The script resembles Western Slavic Latin alphabets but uses circumflexes instead of carons for the letters ĉ, ĝ, ĥ, ĵ, and ŝ. Also, the non-Slavic bases of the letters ĝ and ĵ, rather than Slavic dž and ž, help preserve the printed appearance of Latinate and Germanic vocabulary such as ĝenerala "general" (adjective) and ĵurnalo "journal". The letter v stands for either v or w of other languages. The letter ŭ of the diphthongs aŭ and eŭ resemble the Belarusian Łacinka alphabet.

Zamenhof took advantage of the fact that typewriters for the French language (which, in his lifetime, served as an international lingua franca for educated people) possess a dead key for the circumflex diacritic: thus, anyone who could avail himself of a French typewriter could type ĉ ĝ ĥ ĵ ŝ and their uppercase counterparts with no problem. French typewriters also include the letter ⟨ù⟩, which Francophone Esperantists have long used as a substitute for Esperanto ŭ. With the advent of personal computers, French-language keyboards still possess a dead-key ^, but whether it can be used to type Esperanto consonants may depend on the underlying software. Zamenhof's choice of accented letters was familiar to the speakers of some Slavic languages, for instance, Czech and Slovak, where the sounds of Esperanto ĉ and ŝ are represented by the letters č and š, respectively; and Belarusian, because Esperanto ŭ bears the same relation to u as Belarusian Cyrillic ў bears to у.

Geographic names may diverge from English spelling, especially for the letters x, w, qu and gu, as in Vaŝintono "Washington, D.C.", Meksiko "Mexico City", and Gvatemalo "Guatemala". Other spelling differences appear when Esperanto words are based on the pronunciation rather than the spelling of English place names, such as Brajtono for Brighton.

Variations

Since all letters with diacritics are unique,^{[note 1]} they are often simplified in handwriting. The most common diacritic to be simplified is the circumflex, which often appears more like a macron or acute accent (e.g. ḡ or ǵ instead of ĝ).

Names of the letters of the alphabet

Zamenhof simply tacked an -o onto each consonant to create the name of the letter, with the vowels representing themselves: a, bo, co, ĉo, do, e, fo, etc. The diacritics are frequently mentioned overtly. For instance, ĉ may be called ĉo ĉapela or co ĉapela, from ĉapelo (a hat), and ŭ may be called ŭo luneta or u luneta, from luno (a moon) plus the diminutive -et-. This is the only system that is widely accepted and in practical use.

The letters of the ISO basic Latin alphabet not found in the Esperanto alphabet have distinct names, much as letters of the Greek alphabet do. ⟨q⟩, ⟨x⟩, ⟨y⟩ are kuo, ikso, ipsilono; ⟨w⟩ has been called duobla vo (double V), vavo (using Waringhien's name of va below), vuo (proposed by Sergio Pokrovskij), germana vo (German V), and ĝermana vo (Germanic V).^[5]

However, while this is fine for initialisms such as ktp [kotopo] for etc., it can be problematic when spelling out names. For example, several consonantal distinctions are difficult for many nationalities, who normally rely on the fact that Esperanto seldom uses these sounds to distinguish words (that is, they do not form many minimal pairs). Thus the pairs of letter names ĵo–ĝo, ĥo–ho (or ĥo–ko), co–ĉo (or co–so, co–to), lo–ro, and ŭo–vo (or vo–bo) are problematic. In addition, over a noisy telephone connection, it quickly becomes apparent that voicing distinctions can be difficult to make out: noise confounds the pairs po–bo, to–do, ĉo–ĝo, ko–go, fo–vo, so–zo, ŝo–ĵo, as well as the nasals mo–no.

There have been several proposals to resolve this problem. Gaston Waringhien proposed changing the vowel of voiced obstruents to a, so that at least voicing is not problematic. Also changed to a are h, n, r, distinguishing them from ĥ, m, l. The result is perhaps the most common alternative in use:

a, ba, co, ĉo, da, e, fo, ga, ĝa, ha, ĥo, i, jo, ĵa, ko, lo, mo, na, o, po, ra, so, ŝo, to, u, ŭo, va, za

However, this still requires overt mention of the diacritics, and even so does not reliably distinguish ba–va, co–so, ĉo–ŝo, or ĝa–ĵa.

The proposal closest to international norms (and thus the easiest to remember) that clarifies all the above distinctions is a modification of a proposal by Kálmán Kalocsay. As with Zamenhof, vowels stand for themselves, but it follows the international standard of placing vowel e after a consonant by default (be, ce, de, ge), but before sonorants (el, en) and voiceless fricatives (ef, es). The vowel a is used for ⟨h⟩ and the voiceless plosives ⟨p⟩, ⟨t⟩, ⟨k⟩, after the international names ha for ⟨h⟩ and ka for ⟨k⟩; the French name ĵi is used for ⟨ĵ⟩, the Greek name ĥi (chi) for ⟨ĥ⟩, and the English name ar for ⟨r⟩. The letter ⟨v⟩ has the i vowel of ĵi, distinguishing it from ⟨b⟩, but the other voiced fricative, ⟨z⟩, does not, to avoid the problem of it palatalizing and being confused with ĵi. The diphthong offglide ⟨ŭ⟩ is named eŭ, the only real possibility given Esperanto phonotactics besides aŭ, which as the word for "or" would cause confusion. The letter ⟨m⟩ is called om to distinguish it from ⟨n⟩; the vowel o alliterates well in the alphabetical sequence el, om, en, o, pa. There are other patterns to the vowels in the ABC rhyme: The lines start with a i a i and finish with a a e e. The letters with diacritics are placed at the end of the rhyme, taking the place of w, x, y in other Latin alphabets, so as not to disrupt the pattern of letters many people learned as children. All this makes the system more easily memorized than competing proposals. The modified Kalocsay abecedary is:

a, be, ce, de, e, ef, ge, ha,

i, je, ka, el, om, en, o, pa,

ar, es, ta, u, vi, ĉa, ĝe,

ĥi kaj ĵi, eŝ, eŭ kaj ze,

plus ku', ikso, ipsilono,

jen la abece-kolono.

(kaj means "and". The last line reads: here is the ABC column)

Where letters are still confused, such as es vs eŝ or a vs ha, mention can be made of the diacritic (eŝ ĉapela), or to the manner of articulation of the sound (ha brueta "breathy aitch"). Quite commonly, however, people will use the aitch as in house strategy used in English.

Spelling alphabets

Another strategy is to use a spelling alphabet (literuma alfabeto), which substitutes ordinary words for letters. The following words are sometimes seen:

From a German–Esperanto dictionary by Erich-Dieter Krause:^[6]

Asfalto, Barbaro, Centimetro, Ĉefo, Doktoro, Elemento, Fabriko, Gumo, Ĝirafo, Hotelo, Ĥaoso, Insekto, Jubileo, Ĵurnalo, Kilogramo, Legendo, Maŝino, Naturo, Oktobro, Papero, Kuo, Rekordo, Salato, Ŝilingo, Triumfo, Universo, Universo-hoketo, Vulkano, Ĝermana vo, Ikso, Ipsilono, Zinko ^{[note 2]}

A proposal by Simon Edward Adrian Payne in Monato:^[7]

akvo, baldaŭ, cedro, ĉirkaŭ, dolĉa, eĥo, fajfi, golfo, ĝis, hejme, ĥoro, iĝi, jaĥto, ĵuri, korpo, lingvo, morgaŭ, nokto, ofte, pelvo, kuo, riĉa, sankta, ŝaŭmi, tempo, uzi, ŭa-ŭa, vespo, vavo, ikso, ipsilono, zorgi ^{[note 3]}

A proposal by Gerrit François Makkink, in which most words are tetrasyllabic so that the syllable beginning with the letter in question receives secondary stress (though only in Varsovio do both stressed syllables begin with the letter):^[8]

Akademio, bondeziro, centjariĝo, Ĉe-metodo, delegito, Esperanto, Fundamento, gramatiko, ĝisrevido, harmonio, ĥorkantado, internacia, jubileo, ĵurnalisto, kalendaro, Ludoviko, modernigo, necesejo, okupita, propagando, kuo, redaktoro, sekretario, ŝatokupo, telefono, universala, u-supersigno, Varsovio, vuo, ikso, ipsilono, Zamenhofo

The International League of Esperantist Radio Amateurs (ILERA) uses the following adaptation of the International Radiotelephony Spelling Alphabet (ICAO and NATO "phonetic" alphabet):

alfa, bravo, carli, delta, eko, fokstrot, golf, hotel, india, juliet, kilo, lima, majk, november, oskar, papa, kebek, romeo, siera, tango, uniform, viktor, ŭiski ~ viski, eksrej, janki, zulu

ILERA also modifies the numerals ses '6' and sep '7' to sis and sepen to make them more distinct, and uses the nominal form nulo for zero.

ASCII transliteration

There are two common conventions for inputting and typesetting Esperanto in the ISO basic Latin alphabet when proper orthography is inconvenient. Zamenhof had suggested replacing the circumflex letters with digraphs in h, the so-called "h-system", thus: ch, gh, hh, jh, sh for ĉ, ĝ, ĥ, ĵ, ŝ and u for ŭ, with an apostrophe or hyphen to disambiguate actual sequences of these letters (e.g. ses-hora).^[9] With the advent of computer word-processing, the so-called "x-system", with digraphs in x for all diacritics, has become equally popular: cx, gx, hx, jx, sx, ux. The words ŝanĝi "to change" and ĵaŭde "on Thursday" are written shanghi, jhaude and sxangxi, jxauxde, respectively, in the two systems. The h-system has a more conventional appearance, but because the letter x does not occur in Esperanto, it is fairly straightforward to automatically convert text written in the x-system into standard orthography; it also produces better results with alphabetic sorting.

Capitalization

Capitalization is used for the first word of a sentence and for proper names when used as nouns. Names of months, days of the week, ethnicities, languages, and the adjectival forms of proper names are not typically capitalized (anglo "an Englishman", angla "English", usona "US American"), though national norms may override such generalizations. Titles are more variable: both the Romance style of capitalizing only the first word of the title and the English style of capitalizing all lexical words are found.

All capitals or small capitals are used for acronyms and initialisms of proper names, like TEJO, but not common expressions like ktp (etc.). Small capitals are also a common convention for family names, to avoid the confusion of varying national naming conventions: Kalocsay Kálmán, Leslie Cheung Kwok Wing.

Camel case, with or without a hyphen, may occur when a prefix is added to a proper noun: la geZamenhofoj (the Zamenhofs), pra-Esperanto (Proto-Esperanto). It is also used for Russian-style syllabic acronyms, such as the name ReVo for Reta Vortaro ("Internet Dictionary"), which is homonymous with revo (dream). Occasionally mixed capitalization will be used for orthographic puns, such as espERAnto, which stands for the esperanta radikala asocio (Radical Esperanto Association).

Zamenhof contrasted informal ci with formal, and capitalized, Vi as the second-person singular pronouns. However, lower-case vi is now used as the second-person pronoun regardless of number.