Which term refers to the smallest unit of sound that can distinguish meaning in a language?

• A. Phoneme
• B. Morpheme
• C. Allophone
• D. Syllable

Answer: (A)

Phoneme is the smallest unit of sound that can distinguish meaning in a language. These are the mental categories listeners use to tell words apart; a difference between phonemes changes meaning, as in pat versus bat, where the sounds /p/ and /b/ create different words. Sounds that are just variations of the same phoneme, like the aspirated and unaspirated p in different contexts, are allophones and do not by themselves change meaning. Morpheme is the smallest unit of meaning, not just sound, so it can include whole words or affixes. A syllable is a unit of organization within a word and doesn't necessarily correspond to a contrastive sound, so it isn't about changing meaning by itself.