Definition - The smallest unit of meaningful sound. As opposed to the phone, which is the smallest unit of sound.

1. By convention, phonemes are displayed between slashes ( /b/), whereas phones are bracketed ( [b]).

Example -
In the words lap and lab the /p/ and /b/ are phonemes. However, in the words lap and plug, though the two p's represent different sounds and are, thus, represented by two different phones, they both are still represented by the same phoneme.

Etymology -
The word derives from the French phonème, which in turn derives from the Greek phonema, a sound made, voice, from phone, sound or voice. (For further info, see feedback comment 1 below.)

Oxford English Dictionary -
Its first citation is from 1896:
"There are a few of these terms which the author … still thinks valuable and retains. One of these is the term phoneme, invented by Kruszewski…. I take it that the various sounds which are accepted as identical by any speaking community are one phoneme, though they may differ considerably in actual sound."
(R. J. Lloyd in Die Neueren Sprachen III. 615)


1. The term phoneme was not invented by Kruszewski (as claimed in the quote from OED) but was first used for a sound segment by Antoni Dufriche-Desgenettes in the early 1860s (in the French form phonème).
(mugdan at

2. I think it's important to make clear that a phoneme is not a sound, as the quotation from the OED implies. The phoneme is a collection of sounds heard as one unit by the speakers of the language--something not clear from the example given.
(Betsy Rodriguez-Bachiller, Scotch Plains, NJ)

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