• (n.) A sleight-of-hand trick played with three small cups, shaped like thimbles, and a small ball or little pea. • (v. t.) To swindle by means of small cups or thimbles, and a pea or small ball placed under one of them and quickly shifted to another, the victim laying a wager that he knows under which cup it is; hence, to cheat by any t... Found on http://thinkexist.com/dictionary/meaning/thimblerig/
Thim'ble·rig` noun A sleight-of-hand trick played with three small cups, shaped like thimbles, and a small ball or little pea. Found on http://www.encyclo.co.uk/webster/T/44