CONSONANT, a. 1. Agreeing; according; congruous; consistent; followed generally by to; sometimes by with; as, this rule is consonant to scripture and reason. 2. In music, composed of consonances; as consonant intervals. CONSONANT, n. A letter, so named because it is considered as being sounded only in connection with a vowel. But some consonants have no sound, even when united with a vowel, and others have a very imperfect sound. The consonants are better called articulations, as they are the names given to the several closings or junctions of the organs of speech, which precede and follow the openings of the organs, with which the vowels are uttered. These closings are perfect, and wholly intercept the voice, as in the syllables ek, ep, et; or imperfect, and admitting some slight sound, as in em, en. Hence some articulations are called mutes, and others, semi-vowels. The consonants begin or end syllables, and their use is to determine the manner of beginning or ending the vocal sounds. These closings or configurations of the organs being various, serve to diversify the syllables, as in uttering ba, da, pa, or ab, ad, ap; and although b and p may be considered as representing no sounds at all, yet they so modify the utterance of ab, ap, or ba, pa, that the slight difference between these articulations may be perceived as far as the human voice can be distinctly heard.