old maid

noun6

1. •
   (offensive) An old woman who has never married; a spinster.

   • If she is looking for the perfect man before she marries, she'll be an old maid.
2. •
   A card game in which cards must be paired and one unmatchable card is designated "old maid".
3. •
   An unpopped kernel in a batch of popped popcorn kernels.

   • Crawford asked Congress to double funding for the FDA's $200 million old-maid-elimination research project. — 2004
4. •
   The unmatchable card in that game.
5. •
   The common zinnia.

   • Zinnias are sometimes known as "Old Maids" in the South. — 1989
6. •
   The Madagascar periwinkle.

   • The following are the only hardy species grown, but V. rosea, with rosy or white flowers, is a pretty greenhouse plant known as ' Old Maid ' or ' Madagascar Periwinkle'. — 1901

noun2

1. •
   A children's card game, sometimes played with a special deck, where the object of the game is for each player to find matches for all the cards in his hand, without being stuck with the single unmatchable card.

   • The only card games I know are Go Fish and Old Maid.
2. •
   The unmatchable card itself.

   • The Joker will serve as the Old Maid.