Some part of the articulating organs, as the lips, or the tongue and palate, closed (a) so as to cut off the passage of breath or voice through the mouth and the nose (distinguished as a lip-stop, or a front-stop, etc., as in p, t, d, etc.), or (b) so as to obstruct, but not entirely cut off, the passage, as in l, n, etc.; also, any of the consonants so formed.