The tables below show theequivalents for Latin sounds.
Classical Latin had both long and short vowels. For all vowels besides /a a:/, the short and long versions also had markedly different quality, in most phonological environments. The short vowels were considerably more open. This resulted later in the merging of short i and u with long e and o in Italian, when phonemic vowel length was lost.
|Phonemic notation||100AD Phonetic notation||100BC Phonetic notation|
|a||in all cases||/a/||[a]||[a]|
|?||in all cases||/a:/||[a:]||[a:]|
|e||in most cases||/e/||[?]||[e]|
|before a vowel||[e] or [i]?||[e]|
|?||in all cases||/e:/||[e:]||[e:]|
|i||in most cases||/i/||[?]||[i]|
|before a vowel||[i]||[i]|
|?||in all cases||/i:/||[i:]||[i:]|
|o||in all cases||/o/||[?]||[o]|
|?||in all cases||/o:/||[o:]||[o:]|
|u||in all cases||/u/||[?]||[u]|
|?||in all cases||/u:/||[u:]||[u:]|
|y||in all cases||/y/||[y] or [?]?||non-existent|
|?||in all cases||/y:/||[y:]||non-existent|
Note the inverted breve, which indicates that the vowel does not form a separate syllable.
In Latin, the letter written as I in ancient times was either a vowel or a consonant, or rarely a sequence of consonant and vowel, depending on position and the word, the vowel being most common. The two forms had different pronunciation and different metrical treatment in poetry.
An early modern typographical convention (originating in medieval scripts) is to write J for the consonant form and leave I for the vowel. This is applied both to ordinary words and proper nouns. A similar modern convention exists in writing the vowel V as U (see U and V for more). But while U is very commonly written, the use of J is more variable.
Generally speaking, modern Latin-English dictionaries always use I; however, in the 19th and early 20th centuries the use of J was more widespread (for example, the substantial 1879 dictionary of Lewis and Short). Reprints of classical works on the other hand sometimes write J and sometimes write I. Ecclesiastical works use J more commonly than scholarly classical works, but not to the exclusion of I.
The exclusive use of I never results in ambiguity about the identity of a word, as there are no words that are distinguished solely by the use of I versus J (unlike U versus V; see below).
As a vowel,
As a consonant,
As a consonant–vowel sequence
In Latin, the letter written as V in ancient times represented either a vowel or a consonant depending on its position and the word. These two forms had distinct pronunciations and different metrical treatment in poetry.
A modern typographical convention is to write U for the vowel and leave V as the consonant. Generally speaking dictionaries write U this way and the majority of reprints of classical texts adapt them and show U too. The use of V for the vowel in new works is usually a deliberately classical style or appearance, and that includes for example in inscriptions on new monuments and the like.
Note that there are words where V and U contrast: servit is the third-person singular present of servi?, pronounced /'ser.wit/ in two syllables; while seruit is the third-person singular perfect of ser?, pronounced /'se.ru.it/ in three syllables.
Some example entries for Latin pronunciation given in IPA.