(in English articulation) a speech sound produced by occluding with or without releasing (p, b; t, d; k, g), diverting (m, n, ng), or obstructing (f, v; s, z, etc.) the flow of air from the lungs (opposed to vowel).
(in a syllable) any sound other than the sound of greatest sonority in the syllable, as b, r, and g in brig (opposed to sonant).
c.1300, from L. consonantem (nom. consonans), prp. of consonare "to sound together," from com- "with" + sonare, from sonus "sound" (see sound (n.1)). Consonants thought of as sounds that are only produced together with vowels.