1. any of various long-tailed, medium-sized members of the order primates, including the macaques, baboons, guenons, capuchins, marmosets, and tamarins and excluding the anthropoid apes and the prosimians.
2. one who behaves in a way suggestive of a monkey, as a mischievous child or a mimic.
3. the iron block of a pile driver.
4. slang A person who is mocked, duped, or made to appear a fool: they made a monkey out of him.
5. slang drug addiction: have a monkey on one's back.
6. informal to play, fiddle, trifle, or tamper with something.
7. informal to behave in a mischievous or apish manner: stop monkeying around!
8. to imitate or mimic; ape.

1. any member of the clade Simiiformes not also of the clade hominoidea containing humans and apes, from which they are usually, but not universally, distinguished by smaller size, a tail, and cheek pouches.
2. A mischievous child.
3. five hundred pounds sterling.
4. A person or the role of the person on the sidecar platform of a motorcycle involved in sidecar racing.
5. A person with minimal intelligence and/or (bad) looks.
6. A face card.
7. A menial employee who does a repetitive job.
8. to meddle; to mess with; to interfere; to fiddle.

1.
2. in the most general sense, any one of the Quadrumana, including apes, baboons, and lemurs.
3. any species of Quadrumana, except the lemurs.
4. any one of numerous species of Quadrumana (esp. such as have a long tail and prehensile feet) exclusive of apes and baboons.
5. A term of disapproval, ridicule, or contempt, as for a mischievous child.
6. the weight or hammer of a pile driver, that is, a very heavy mass of iron, which, being raised on high, falls on the head of the pile, and drives it into the earth; the falling weight of a drop hammer used in forging.
7. A small trading vessel of the sixteenth century.
8. to act or treat as a monkey does; to ape; to act in a grotesque or meddlesome manner.

1. to act in an idle or meddlesome manner; trifle; fool: as, don't monkey with that gun.
2. to imitate as a monkey does; ape.
3. A quadrumanous mammal of the order primates and suborder anthropoidea; a catarrhine or platyrrhine simian; any one of the primates except man and the lemurs; an ape, baboon, marmoset, etc.
4. an epithet applied to any one, especially to a boy or girl, in either real or pretended disapproval: sometimes expressing endearment.
5. A pile-driving instrument with two handles, raised by pulleys, and guided in its descent so as to cause it to fall on the head of a pile and drive it into the ground; a fistuca; a beetlehead.
6. A sort of power-hammer used in ship-building for driving bolts, composed of a long pig of iron traversing in a groove, which is raised by pulleys, and let fall on the spot required.
7. A small crucible used in glass-making.
8. A certain sum of money: in the united states, $500; in great britain, £500: used especially in betting.
9. A kind of bustle formerly worn by women. see the quotation.
10. same as water-monkey.
11. A fluid composed of two parts of chlorhydric acid (generally called spirits of salt by workmen) and one part of zinc, used in soldering.
12. to drink rum or other liquor.
13. in mining, an appliance for automatically gripping or letting go the rope in rope haulage.
14. plural in the australian bush, a sheep-shearer's name for sheep.
15. A local name for the cinder-notch of the dam in an iron-making blast-furnace, through which the slag or cinder can be allowed to flow out as it accumulates in the smelting process. it is placed on the side of the furnace, and about 30 or 40 inches below the level of the twyers where the blast is introduced in furnaces of modern size.

1. one who is playfully mischievous
2. do random, unplanned work or activities or spend time idly
3. play around with or alter or falsify, usually secretively or dishonestly
4. any of various long-tailed primates (excluding the prosimians)