A syllabic consonant is a consonant which either forms a syllable on its own, like the m, n and l in the English words rhythm, button and bottle, or is the nucleus of a syllable, such as the r sound in the American pronunciation of work. The diacritic for this in the International Phonetic Alphabet (IPA) is the under-stroke, . It may be represented by an over-stroke, , if the symbol that it modifies has a descender, such as in .

• Most languages that have syllabic consonants have syllabic sonorants such as nasals and liquids. A very few have syllabic obstruents such as stops and fricatives in normal words, though English has syllabic fricatives in paralinguistic words like shh! and zzz.