a. 乳头状的

n. 乳突

[医] 乳头状的, 乳突, 乳突的

Mastoid \Mas"toid\, a. [Gr. ?; masto`s the breast + e'i^dos
form: cf. F. masto["i]de.] (Anat.)
(a) Resembling the nipple or the breast; -- applied
specifically to a process of the temporal bone behind the
ear.
(b) Pertaining to, or in the region of, the mastoid process;
mastoidal.