Consonants

Consonants are speech sounds that (1) involve an obstruction or near obstruction to an egressive airflow through the oral cavity (thus unlike vowels) and (2) do not normally constitute a syllabic nucleus (except a few syllabic consonants discussed later). However, this description combines phonetic characteristics (Part 1) with phonological ones (Part 2). Therefore, some researchers prefer to use the term contoid (as opposed to vocoid) for the purely phonetic definition and consonant for the phonological one. This entry explains consonant production, describes consonants by articulation and acoustically, and discusses consonants in disordered speech.

Thus, [t] would be a contoid, and a consonant [j] would be a vocoid and a consonant, whereas syllabic nasals would arguably be contoids phonetically (as they involve a complete obstruction in the ...