A phonemic orthography is a writing system where the written graphemes correspond to phonemes, the spoken sounds of the language. These are sometimes termed true alphabets, but non-alphabetic writing systems like syllabaries can be phonemic as well.
Phonemic orthography in a language is affected by the borrowing of loanwords from another written in the same alphabet but having different sound-to-spelling conventions. If the original spelling and pronunciation are both kept, then the spelling is "irregular": for example, fajita is pronounced as [fəˈhiɾə] to reflect the Spanish pronunciation of [faˈxita] rather than as [fəˈdʒaɪɾə] as the spelling would suggest under normal English spelling rules. Phonemicity may be preserved by nativizing the loanword's pronunciation as with the Russian word шофёр (from French chauffeur) which is pronounced [ʂɐˈfʲor] in accordance with the normal rules of Russian vowel reduction. Spelling pronunciation is another common phenomenon, such as the word Iraq which many English speakers pronounce with a voicless velar plosive/k/ rather than a voiceless uvular plosive/q/. Nativizing the spelling of loanwords is also common; for example, uísque is the Portuguese spelling of whisky, itself a respelling of Scots Gaelicuisge).
Difference from phonetic transcription
Methods for phonetic transcription such as the International Phonetic Alphabet (IPA) aim to describe pronunciation in a standard form. They are often used to solve ambiguities in the spelling of written language. They may also be used to write languages with no previous written form. Systems like IPA can be used for phonemic representation or for showing more detailed phonetic information (see Narrow vs. broad transcription).
Phonemic orthographies are different from phonetic transcription; whereas in a phonemic orthography, allophones will usually be represented by the same grapheme, a purely phonetic script would demand that phonetically distinct allophones be distinguished. To take an example from American English: the /t/ sound in the words "table" and "cat" would, in a phonemic orthography, be written with the same character; however, a strictly phonetic script would make a distinction between the aspirated "t" in "table", the flap in "butter", the unaspirated "t" in "stop" and the glottalized "t" in "cat" (not all these allophones exist in all English dialects). In other words, the sound that most English speakers think of as /t/ is really a group of sounds, all pronounced slightly differently depending on where they occur in a word. A perfect phonemic orthography has one letter per group of sounds (phoneme), with different letters only where the sounds distinguish words (so "bed" is spelled differently from "bet").
A narrow phonetic transcription represents phones, the atomic sounds humans are capable of producing, many of which will often be grouped together as a single phoneme in any given natural language, though the groupings vary across languages. English, for example, does not distinguish between aspirated and unaspirated consonants, but other languages, like Bengali and Hindi, do.
