Up one’s sleeve
The notion of keeping something up one’s sleeve as a fallback safeguard or a surprise alternative dates back to the 1500s at least, and all such expressions had literal origins. Thus card players who wished to cheat would keep an ace up the sleeve while magicians honestly plying their trade would keep tricks up their sleeves. The practice of keeping something up one’s sleeve was made easier by the fashions of earlier centuries, which favoured voluminous, wide sleeves. One could even laugh in one’s sleeve at someone, without them being aware, because wide sleeves made this possible. John Daus, who translated the Sleidanes Commentaries (1560) from Latin into English wrote, “If I coveted now to avenge the injuries that you have done to me, I might laugh in my sleeve.” Molière uses the same expression, though in French, in his play Tartuffe (1664) Act I, Scene I. In Sheridan’s The Rivals (1774) Act II, Scene I, Mrs Malaprop says, “I know you are laughing in your sleeve.” Most of these ‘up one’s sleeve’ expressions, in the figurative sense, date from at least the 16th century.