deuce

Concise Oxford English Dictionary © 2008 Oxford University Press:
deuce1 /djuːs/

▶noun

• 1 chiefly N. Amer. a thing representing, or represented by, the number two, in particular the two on dice or playing cards.

• 2 Tennis the score of 40 all in a game, at which each player needs two consecutive points to win the game.

– origin C15: from OFr. deus ‘two’, from L. duos.

Concise Oxford English Dictionary © 2008 Oxford University Press:
deuce2 /djuːs/

▶noun (the deuce) informal used as a euphemism for ‘devil’ in exclamations or for emphasis.

– origin C17: from Low Ger. duus, prob. of the same origin as deuce1 (two aces at dice being the worst throw).