mastoid

剑桥词典

relating to the mastoid process (= part of the skull just behind the ear )
乳突骨
Mastoidectomy is performed to remove infected air cells within the mastoid bone . 乳突切除術是指移除乳突骨內被感染的氣房。

shaped like a breast or a nipple (= one of the two small darker parts that stick out from the breasts or chest )
乳房狀的；乳頭狀的 返回 mastoid