Which term refers to the smallest unit of sound in a language?

The term that refers to the smallest unit of sound in a language is phonemes. Phonemes are the distinct units of sound that can distinguish one word from another within a language. For example, the words "bat" and "pat" differ only in their initial phonemes /b/ and /p/. This concept is fundamental in phonetics and phonology, which are key areas of linguistics that study the sounds of languages.

Syllables, on the other hand, are larger units of sound that consist of a vowel sound and can include consonants; they cannot distinguish words as finely as phonemes. Morphemes represent the smallest units of meaning in a language, including prefixes, roots, and suffixes, which can combine to form meaningful words. Words are larger, complete units of language that convey meaning but encompass multiple phonemes and morphemes. Thus, phonemes specifically capture the smallest sound distinctions necessary for language processing and comprehension.