Games A suit in card games that outranks all other suits for the duration of a hand. Often used in the plural. Games A card of such a suit. Games A trump card. A key resource to be used at an opportune moment. Informal A reliable or admirable person. Games To take (a card or trick) with a trump. To get the better of (an adversary or competitor, for example) by using a crucial, often hidden resource. Games To play a trump. trump up To devise fraudulently: trumped up a charge of conspiracy. A trumpet.