consonant

n. letter (in the alphabet) that is not a vowel

Not to be confused with the musical concept of consonance. In articulatory phonetics, a consonant is a sound in spoken language that is characterized by a closure or stricture of the vocal tract sufficient to cause audible turbulence. The word consonant comes from Latin and means "sounding with" or "sounding together," the idea being that consonants don't sound on their own, but occur only with a nearby vowel, which is the case in Latin. This conception of consonants, however, does not reflect the modern linguistic understanding which defines consonants in terms of vocal tract constriction.
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adj. consonant

n. consonant, letter (in the alphabet) that is not a vowel

(n.)
An articulate sound which in utterance is usually combined and sounded with an open sound called a vowel; a member of the spoken alphabet other than a vowel; also, a letter or character representing such a sound.
  

(a.)
Of or pertaining to consonants; made up of, or containing many, consonants.
  

(a.)
Having like sounds.
  

(a.)
Having agreement; congruous; consistent; according; -- usually followed by with or to.
  

(a.)
harmonizing together; accordant; as, consonant tones, consonant chords.