n. (Bot.) The name of several plants of the genera Spermacoce and Diodia, of the Madder family. [ 1913 Webster ]
adj. furnished with buttons or something buttonlike. Opposite of unbuttoned. [ Narrower terms: botonee, botonnee; button-down; closed ] [ WordNet 1.5 ]
adj. conservatively formal and businesslike in dress and manner. Syn. -- button-down, conservative. [ WordNet 1.5 ]
a colorful character in the buttoned-down, dull-gray world of business. Newsweek
adj. 1. taciturn. Opposite of voluble. [ British colloquial ] [ WordNet 1.5 ]
2. conservative in professional manner; as, employers are looking for buttoned-up types. [ WordNet 1.5 ]