[n] any of various long-tailed primates (excluding the prosimians)
[n] one who is playfully mischievous
[v] do random, unplanned work or activities or spend time idly; "The old lady is usually mucking about in her little house"
[v] fool or play around with; "Someone tampered with the documents on my desk"
imp, mess around, monkey around, muck about, muck around, potter, putter, rapscallion, rascal, scalawag, scallywag, scamp, tamper, tinker