A monkey their back

[muhng-kee] /ˈmʌŋ ki/
noun, plural monkeys.
any mammal of the order primates, including the guenons, macaques, langurs, and capuchins, but excluding humans, the anthropoid apes, and, usually, the tarsier and prosimians.
compare new world monkey, old world monkey.
the fur of certain species of such long-haired animals.
a person likened to such an animal, as a mischievous, agile child or a mimic.
a dance, deriving from the twist, in which the partners move their hands as if climbing a pole and jerk their heads back and forth.
slang. an addiction to narcotics.
any of various mechanical devices, as the ram of a pile driver.
coal mining. a small p-ssageway or opening.
british slang. the sum of 500 pounds.
australian informal. a sheep.
verb (used without object), monkeyed, monkeying.
informal. to play or trifle idly; fool (often followed by around or with).
verb (used with object), monkeyed, monkeying.
to imitate; ape; mimic.
to mock.
idioms
a monkey on one’s back, slang.

an addiction to a drug or drugs; narcotic dependency.
an enduring and often vexing habit or urge.
a burdensome problem, situation, or responsibility; personal affliction or hindrance.

make a monkey out of, to cause to appear ridiculous; make a fool of.
also, make a monkey of.
related forms
monkeyish, adjective
monkeyishly, adverb
monkeyishness, noun
monkey
/ˈmʌŋkɪ/
noun
any of numerous long-tailed primates excluding the prosimians (lemurs, tarsiers, etc): comprise the families cercopithecidae (old world monkeys), cebidae (new world monkeys), and callithricidae (marmosets) see old world monkey, new world monkey related adjective simian
any primate except man
a naughty or mischievous person, esp a child
the head of a pile-driver (monkey engine) or of some similar mechanical device
(modifier) (nautical) denoting a small light structure or piece of equipment contrived to suit an immediate purpose: a monkey foresail, a monkey bridge