A serious problem that won’t go away or is difficult to get rid of.
The origin of the phrase is uncertain. Some scholars believe that the original expression was ‘have a monkey on the roof’ which was used in the 1800s to refer to the mortgage that had to be paid. And we’re all aware of the burden of mortgage payments which plague most house owners today. During the 1940s, ‘monkey on the back’ acquired a new meaning — someone who had a monkey on his back was addicted to drugs.
The earliest references to piggybacking monkeys involve other animals. In 1807, sportswriter Pierce Egan wrote of a monkey riding a horse. This seems relevant because of its proximity in time to the phrase first being used figuratively for mortgages and because the monkey is either frightening the horse or symbolizing its subjugation.
In 1822, Thomas Gillett published a collection of stories as The Midland Minstrel that included a humorous tale called “The Devil and the Doctor” about some students who teach their overzealous instructor a lesson by dropping a monkey on his back while he’s riding his horse home one night. He’s convinced the monkey is the devil and, after a mad dash through town, sees the error of his ways. This attribution of evil to the monkey is, of course, significant.
A much more ancient tale involving a monkey on somebody else’s back is a fable by Aesop, who lived circa 620–564 BCE. The title is “The Monkey and the Dolphin.” A ship, which contains several crew members and a monkey that belongs to one of them, founders in a storm and everyone tries to swim ashore. A dolphin sees the monkey, thinks it’s a man, and carries the monkey on its back safely to shore. However, the monkey tells several lies and the dolphin ends up drowning it. They exercised rough justice 2500 years ago!
It appears that the use of ‘monkey on your back’ for opiate addiction was a natural evolution of the phrase from its history of referring to an evil force acting to subjugate someone.
I’m glad I don’t have a monkey on my back; they’re so darn noisy!