ace (plural aces) (card games) A playing card showing a single pip, typically the highest or lowest ranking card in a game. quotations An ace is a playing card with the highest value in a deck . There are four aces in a full deck of cards, each with a single heart, spade, diamond, or club pictured on it. ace meaning , definition , what is ace : a playing card with a single spot on it,...: Learn more. Ace can be a noun, adjective, or verb with various meanings related to cards, games, sports, or excellence. Learn the different senses, examples, and idioms of ace from The Free Dictionary.