phonemic transcription
Phonemic transcription is the most common type of phonetic transcription, used in many English dictionaries.
How does phonemic transcription work? Suppose we have two different English sounds. Should we give them separate symbols in transcriptions? In phonemic transcription, the answer is "yes" only if there is an English word where saying one sound instead of another changes the meaning.
For example, saying "d" instead of "t" in the word bet changes the meaning (the word becomes bed), therefore we use separate symbols for "d" and "t" in phonemic transcriptions. In other words, we say that "t" and "d" are two separate phonemes.
On the other hand, the "flap t" (in this pronunciation of the word letter) and the regular "t" (in this one) are two very different sounds. However, there are no English words where saying the "flap t" instead of the regular "t" (or the other way around) changes the meaning. Therefore, in phonemic transcription, we use the same symbol for the "flap t" and the regular "t". In other words, we say that the "flap t" and the regular "t" are the same phoneme.
More examples
Each of these examples gives two different sounds that are written with the same symbol in phonemic transcription. In other words, the two sounds are the same phoneme.
- the "clear l" in lean and the "dark l" in hill (the second sounds like a vowel and the tongue does not touch the top of your mouth; the difference is especially audible in British English)
- the "ee" sound in this pronunciation of meet and this one (the second is much longer)
- the "p" sound in pin and spin (the first is accompanied by more breathing)
- the "w" sound in wet and twice (the first is voiced, the second is not)
A. C. Gimson's system
The most popular system of phonemic transcription was created by A. C. Gimson, the editor of the 13th edition of the English Pronouncing Dictionary, published in 1967. It is used (usually with certain small changes) in nearly all dictionaries published in Britain.
Gimson's system uses symbols from the International Phonetic Alphabet (IPA) to
represent phonemes. Of course, some phonemes can be pronounced in many ways
(as explained above), and therefore could be written with many IPA symbols.
For example, the "t" phoneme can be spoken like the "regular t"
(IPA symbol 
) or like
the "flap t" (IPA symbol 
).
In such cases, A. C. Gimson simply chose one of the possible IPA symbols.
Thus, the "t" phoneme is represented by the symbol.
For more information on phonemic transcription as it is used in modern dictionaries, see our introduction to phonetic transcription and our table with symbols used in phonemic transcriptions in dictionaries.