#1 old maid n. an elderly unmarried woman. wn #2 old maid n. any of various plants of the genus Zinnia cultivated for their variously and brightly colored flower heads. wn #3 old maid n. commonly cultivated Old World woody herb having large pinkish to red flowers. wn #4 old maid n. the loser in a game of old maid. wn #5 old maid n. a card game using a pack of cards from which one queen has been removed; players match cards and the player holding the unmatched queen at the end of the game is the loser (or 'old maid'). wn