• (a.) Formed by the lips and the nose. • (n.) A labionasal sound or letter.
1. Relating to the upper lip and the nose, or to both lips and the nose. ... 2. Denoting a letter which is both labial and nasal in the production of its sound. ... (05 Mar 2000) ... 
(la″be-o-na´zәl) pertaining to the lips and nose.
La`bi·o·na'sal adjective [ Labium + nasal .] (Phonetics) Formed by the lips and the nose. -- noun A labionasal sound or letter. 
Type: Term Pronunciation: lā′bē-ō-nā′săl Definitions: 1. Relating to the upper lip and the nose, or to both lips and the nose. 2. Denoting a letter that is both labial and nasal in the production of its sound.