n. & adj.
n. 1 (as a title Cardinal) a leading dignitary of the RC Church, one of the college electing the Pope. 2 any small American songbird of the genus Richmondena, the males of which have scarlet plumage. 3 hist. a woman's cloak, orig. of scarlet cloth with a hood.
adj. 1 chief, fundamental; on which something hinges. 2 of deep scarlet (like a cardinal's cassock). cardinal-flower the scarlet lobelia. cardinal humour see HUMOUR. cardinal numbers those denoting quantity (one, two, three, etc.), as opposed to ordinal numbers (first, second, third, etc.). cardinal points the four main points of the compass (N., S., E., W.). cardinal virtues the chief moral attributes: justice, prudence, temperance, and fortitude. cardinalate n. (in sense 1 of n.). cardinally adv. cardinalship n. (in sense 1 of n.).
[ ME f. OF f. L cardinalis f. cardo -inis hinge: in Eng. first applied to the four virtues on which conduct 'hinges' ]