Terminology
The word consonant comes from Latin oblique stem cōnsonant-, from cōnsonāns (littera) "sounding-together (letter)", a calque of Greek σύμφωνον sýmphōnon (plural sýmphōna).
Dionysius Thrax calls consonants sýmphōna "pronounced with" because they can only be pronounced with a vowel. He divides them into two subcategories: hēmíphōna, semivowels ("half-pronounced"), which correspond to continuants, not semivowels, and áphōna, mute or silent consonants ("unvoiced"), which correspond to stops, not voiceless consonants.
This description does not apply to some human languages, such as the Salishan languages, in which stops sometimes occur without vowels (see Nuxálk), and the modern conception of consonant does not require cooccurrence with vowels.
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