From WordNet (r) 3.0 (2006):
monkey n 1: any of various long-tailed primates (excluding the prosimians) 2: one who is playfully mischievous [syn: imp, scamp, monkey, rascal, rapscallion, scalawag, scallywag] v 1: play around with or alter or falsify, usually secretively or dishonestly; "Someone tampered with the documents on my desk"; "The reporter fiddle with the facts" [syn: tamper, fiddle, monkey] 2: do random, unplanned work or activities or spend time idly; "The old lady is usually mucking about in her little house" [syn: putter, mess around, potter, tinker, monkey, monkey around, muck about, muck around]