definition of
twenty-one

[1] #1 twenty-one s. [21, xxi] being one more than twenty. wn

[2] #2 twenty-one n. [21, XXI] the cardinal number that is the sum of twenty and one. wn

[3] #3 twenty-one n. [blackjack, vingt-et-un] a gambling game using cards; the object is to hold cards having a higher count than those dealt to the banker up to but not exceeding 21. wn