Estonian orthography is the system used for writing the Estonian language and is based on the Latin alphabet. The Estonian orthography is generally guided by phonemic principles, with each grapheme corresponding to one phoneme.
Alphabet Due to German and Swedish influence, the Estonian alphabet () has the letters Ä, Ö, and Ü (A, O, and U with diaeresis), which represent the vowel sounds , and , respectively. Unlike German umlauts, they are considered, and alphabetised as, separate letters. The most distinctive letter in the Estonian alphabet, however, is the Õ (O with tilde), which was added to the alphabet in the 19th century by Otto Wilhelm Masing and stands for the vowel . In addition, the alphabet also differs from the Latin alphabet by the addition of the letters Š and Ž (S and Z with caron/háček), and by the position of Z in the alphabet: it has been moved from the end to between S and T (or Š and Ž).
The official Estonian alphabet has 27 letters: A, B, D, E, F, G, H, I, J, K, L, M, N, O, P, R, S, Š, Z, Ž, T, U, V, Õ, Ä, Ö, Ü. The letters F, Š, Z, Ž are so-called "foreign letters" (), and occur only in loanwords and proper names.
Additionally, C, Q, W, X, and Y are "foreign letters" used only in writing foreign proper names. These letters do not occur in any Estonian words, and thus are not usually considered part of the "Estonian proper" alphabet. Including all the foreign letters, the entire alphabet consists of the following 32 letters: LetterIPANameNotesLetterIPANameNotesAaaa Qq—kuu Bbbee Rrerr or ärr Cc—tsee Ssess Dddee Šš or šaa Eeee Zzzett Ff or eff Žžžee Gggee Tt or tee Hhhaa or ašš Uuuu Iiii Vvvee Jjjott Ww—kaksisvee Kk or kaa Õõõõ Llell Ääää Mmemm Öööö Nnenn Üüüü Oooo Xx—iks Pp or pee Yy—igrek or üpsilon
In Blackletter script W was used instead of V. In some reference works in the past, V and W were sorted as if they were one and the same letter.
Johannes Aavik suggested that the letter Ü be replaced by Y, as it has been in the Finnish alphabet.
Double letters are used to write half-long and overlong vowels and consonants, e. g. aa or , nn or , kk . For more information, see below.
As the distinction between voiced and voiceless plosives is not native to Estonian, the names of the letters 'b', 'd', 'g' may be pronounced , , , so the letters 'b' and 'd' are also named () and () to distinguish them from () and (). About usage of these letters, see below.
Orthographic principles Although Estonian orthography is generally guided by phonemic principles, with each grapheme corresponding to one phoneme, there are some historical and morphological deviations from this: for example the initial letter h in words, preservation of the morpheme in declension of the word (writing b, g, d in places where p, k, t is pronounced) and in the use of i and j. Where it is impractical or impossible to type š and ž, they are substituted with sh and zh in some written texts, although this is considered incorrect, and may even result in ambiguities, as in (pas-ha) vs. (paša).
Some features of the modern Estonian orthography are: Word-initial b, d, g occur only in loanwords and are normally pronounced as , , . Some old loanwords are spelled with p, t, k instead of etymological b, d, g: 'bank'. Word-medially and word-finally, b, d, g represent short plosives (may be pronounced as partially voiced consonants), p, t, k represent half-long plosives , and pp, tt, kk represent overlong plosives ; for example: 'hoof' — 'wardrobe' [ ] — 'wardrobe [ ]'. Before and after b, p, d, t, g, k, s, h, f, š, z, ž, the sounds , , are written as p, t, k, with some exceptions due to morphology or etymology. For example, the suffixed particle -gi 'too, also' may become -ki, but does not alter the spelling of the stem, so 'desert' + -gi becomes . Word-initial is often dropped in spontaneous speech, but should be represented in writing. The letter j is used at the beginning of syllables, but i is used at the end of syllables. Double j is used only in some illative case forms. The spelling üü before vowels corresponds to the pronunciation : 'to sell' (-da infinitive of 'to sell'). The spelling üi is used only in the loanwords , , . Between i and vowels, the epenthetic sound is pronounced but not written. It is, however, written in the suffix -ja. Vowels and the consonants h, j, l, m, n, r, s, v are written single when they are short, double when they are half-long or overlong: 'blood [ ]' — 'edge [ ]' — 'roll [ ]', 'sheet' — 'town [ ]' — 'town [ ]'. Diphthongs and consonant combinations are written as combinations of single letters, regardless of whether they are pronounced short or long. Only s after l, m, n, r may be doubled if not followed by another consonant ( 'waltz'), otherwise combinations "consonant+double consonant" and "double consonant+consonant" occur only in morpheme boundaries, e. g. 'modern' (-ne is a suffix), 'cardboard box' (from 'cardboard' and 'box'). However, a double consonant at the end of a root is simplified before a suffix beginning with a consonant (except -gi/-ki): 'townsman' (from 'town'). The single word-medial or word-final letters f and š represent half-long consonants , the double letters ff and šš represent overlong consonants . After consonants, f and š are always written single, regardless of whether they are pronounced half-long or overlong. Palatalization is not indicated in writing, e. g. 'jug' — 'toy'. It occurs in words that have i in declension: 'toy [ and ]'. Stress is not indicated in writing. Usually it falls on the first syllable, but there are a few exceptions with the stress on the second syllable: 'thanks', 'female friend'. Often the original stress is preserved in loanwords, such as 'ideal', 'professor'; presence of long vowels (as in ) also shows stress.
Syllabification One consonant between two vowels belongs to the following syllable: 'fish' is syllabified ka-la. Consonant combinations are syllabified before the last consonant: 'town [ ]' is syllabified lin-na, 'acquaintance' is syllabified . Consonant digraphs and trigraphs in foreign names are regarded as single consonants: is syllabified Man-ches-ter. Two vowels usually form a long vowel or a diphthong, e. g. 'song' is syllabified lau-lu. However, a hiatus is formed in morpheme bounds, e. g. 'opening' is syllabified a-va-us as the word is composed from the root ava- and the suffix -us. Combinations of three vowel letters represent a hiatus of a long vowel or a diphthong and another vowel, e. g. 'dry, droughty, arid (lacking rain)' is syllabified põu-a-ne; but some loanwords have a hiatus of a short vowel followed by a long vowel: 'oasis' is syllabified o-aas. Compound words are syllabified as combinations of their parts: 'grandmother' is syllabified as va-na-e-ma as the word is composed from 'old' and 'mother'. Etymologically compound loanwords and foreign names may be syllabified as compound or simple words: 'photographer' is syllabified fo-to-graaf or fo-tog-raaf, is syllabified Pet-ro-grad or Pet-rog-rad.
These syllabification rules are used for hyphenating words at the end of line, with the additional rule that a single letter is not left on a line.
Foreign words Loanwords are normally adapted to Estonian spelling: 'web', 'jazz'. However, foreign words and phrases sometimes may be used in the original spelling, such as Latin phrases, Italian musical terms, exotic words. Such citations are typographically emphasized using italics and declined using an apostrophe: croissant'id 'croissants'.
Foreign proper names from Latin-script languages are written in their original spelling: Margaret Thatcher, Bordeaux. Names from non-Latin-script languages are written using either Estonian orthographic transcription or established romanization systems. Some geographical names (and some names of historical personalities, such as monarchs) have traditional Estonian forms (including some adapted spellings such as for German 'Vienna').
Derivations from foreign proper names with the suffixes -lik, -lane, -lus, -ism, -ist usually conserve the spelling of names (e. g. , ), but a few are adapted by established tradition: , , . Derivations without suffixes or with other suffixes are adapted to Estonian spelling: 'newton' (unit of force), (maxillary sinusitis, inflammation of the antrum of Highmore), 'ytterbium' (chemical element), etc.
Expressions such as 'degree Celsius', 'Cheddar cheese' conserve the spelling of proper names (adding case endings). However, names of plants and animals are usually written in adapted forms, e.g. 'Colorado beetle'.
Apostrophe is used when adding case endings to proper names with unusual grapheme-to-phoneme correspondences (such as ending on a consonant orthographically but on a vowel phonetically or vice versa), e.g. (genitive of Provence).
Capitalization Capital letters are written at the beginning of the first word in a sentence, proper names, and official names functioned as proper names. May be used in the pronouns 'you (singular)' and 'you (plural, also used as formal singular)' to show respect.
Names of months, days of the week, holidays, Chinese zodiac years, and titles of people such as are not capitalized.
Titles of books, films, etc. are written in quotation marks with only the first word and proper names capitalized.
Compound words Compound words are written as one word, but they are often composed of genitive+nominative and hard to distinguish from simple word combinations. A compound word is considered a single word and written together when: 1) it has a separate meaning, e. g. 'chapter' but 'part of a head'; 2) it is different from the genitive+nominative combination, e. g. (nominative+nominative) 'watermill'; 3)some combinations may be together or separately, but writing them together is preferred in more complex word phrases: 'member of a party' — 'every member of the party'. Rare and long word combinations are typically written separately.
The hyphen is used: 1) in compounds where one of the parts is a letter ( 'vitamin C'), an initialism ( 'text TV'), a foreign citation ( 'joke show') or a word part ( 'word containing ); 2) in compound adjectives where the first part as a proper name; 3) in compound geographical names such as 'South Estonia'; 4) as a suspended hyphen, e.g. 'gold and silver things' (also in compound words such as 'export-import bank'); 5) in "nominative+ablative" adverbs, e. g. 'day after day'; 6) in dvandva compounds, e. g. 'father and mother'; 7) in compound adjectives from word phrases, e.g. 'related to tentative phonetics'; 8) in compound adjectives with coordinating meaning, e.g. 'Estonian-English dictionary'; 9) in double names such as . It can be optionally used in unusual compounds such as 'gooseberry disease'; in compounds with three or four identical letters in a row (e. g. 'yearly', 'bone groove'); in compounds with numbers (see below) or with signs (e.g. '+ sign'); in the construction 'genitive of a proper name + nominative' after another genitive (e. g. 'European part of Russia'); in the colloquial construction 'genitive of a proper name + noun' instead of 'noun + proper name', e. g. instead of 'Uncle Kuusk'; in ad hoc compounds such as ; in words from two-or-more-component proper names, e. g. .
Abbreviations The abbreviation period (full stop) may be used, but it is not mandatory. Commonly used abbreviations are usually written without the abbreviation period: , , or for 'street'; for 'see'; for 'and many others'. Using the abbreviation period is recommended when an abbreviation may be misread as another word: for 'figure, draft' but 'line'. If an abbreviation of a word phrase may be mistaken for a word or for another abbreviation, periods are used after every letter but the last one, and spaces are not used: for but 'mother', for but for 'economy'.