consonant

A consonant is a speech sound produced with some obstruction or narrowing of the vocal tract, shaping the flow of air in a way that contrasts with vowels, which are typically more open and sonorous. Consonants are the building blocks of syllables and words in most languages, where they interact with vowels to encode meaning.

Consonants are classified by place and manner of articulation, as well as by voicing. Place of articulation refers to where in the vocal tract the constriction occurs, such as bilabial (both lips), labiodental (lip and teeth), dental, alveolar, post-alveolar, palatal, velar, uvular, and glottal. Manner of articulation describes how airflow is modified, including stops or plosives (p, b, t, d, k, g), fricatives (f, s, h, z), affricates (ts, d͡z), nasals (m, n), liquids (l, r), and approximants (w, j). Consonants can be voiced or voiceless, depending on whether the vocal folds vibrate during articulation. Some languages include additional types such as taps, trills, or lateral consonants, and may use glottal stops or ejectives as phonemic sounds.

Phonotactics and syllable structure determine how consonants can occur within a word. Consonants typically form syllable onsets and codas, and many languages permit consonant clusters at one or both edges of a syllable, following language-specific orderings and constraints. The relative sonority of consonants influences permissible sequences.

Consonants are represented in writing systems by letters and digraphs, with many languages exhibiting large inventories and diverse phonemes. English, for example, includes p, b, t, d, k, g, f, v, s, z, the digraphs sh and ch, and others such as m, n, l, r, w, and y, along with occasional glottal stops in certain dialects. Consonants play a central role in phonology and acquire meaning through their contrasts with vowels and with each other.