1. (n.)monkey any mammal of two major groupings of Primates, the Old World monkeys or catarrhines, and the New World monkeys or platyrrhines, both characterized by flattened faces, binocular vision, and usu. long tails.
8. monkey a burdensome problem, situation, or responsibility.
Etymology: (1950–55)
Definition of 'MONKEY'
Princeton's WordNet
1. (noun)monkey any of various long-tailed primates (excluding the prosimians)
2. (verb)imp, scamp, monkey, rascal, rapscallion, scalawag, scallywag one who is playfully mischievous
3. (verb)tamper, fiddle, monkey 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"
4. (verb)putter, mess around, potter, tinker, monkey, monkey around, muck about, muck around do random, unplanned work or activities or spend time idly "The old lady is usually mucking about in her little house"