The name of the 1980s' most famous one-man army comes from a fruit bowl.
David Morrell was writing First Blood, his 1972 novel about a Vietnam veteran, and had no name for the hero. His wife brought home some apples from a roadside stand. Mental Floss quotes Morrell's own account: he took a bite, found it delicious, and asked what it was called. "'Rambo,' she replied." Then: "Instantly, I recognized the sound of force."
There was a second echo. Morrell had been studying the French poet Arthur Rimbaud. The apple's name, he said, resembled the way some people pronounce the poet's surname.
The apple has its own history. Wikipedia says the origins of the Rambo cultivar are unknown, but it may go back to the colony of New Sweden. A Swedish settler, Peter Gunnarsson, sailed there on the Kalmar Nyckel's second voyage and arrived in early 1640. He took the surname Rambo. A century later the naturalist Pehr Kalm interviewed his grandson, who said the first Rambo had brought apple seeds in a box. The first Rambo tree may have grown from them.
The family name probably comes from Peter Gunnarsson's home at Ramberget, "Raven Mountain," on the island of Hisingen, now part of Gothenburg. The earliest documented mention of the apple is in William Coxe's book of 1817.
One detail is murky. Wikipedia notes it is unclear whether Morrell's apples were true Rambos or Summer Rambos, an unrelated variety also called Rambour Franc, which was more common.
In the novel the hero has no first name. The 1982 film First Blood gave him one, John Rambo, Mental Floss reports. The films that followed made the surname a common noun. The Oxford Learner's Dictionaries define a rambo as "a very strong and aggressive man," citing Morrell's 1972 novel as the source.
So the word for a one-man army began as the name of an apple that a Swedish colonist may have planted in America.