the.com/urban legend

means A widely circulated, often lurid story presented as true that spreads through word of mouth and shares the structure of a tale — a plot, a warning, a twist — rather than verified facts.

from The phrase was popularized by folklorists in the mid-20th century, especially through Jan Harold Brunvand's work in the 1980s, as a label for modern oral tales — vanishing hitchhikers, alligators in sewers, poisoned Halloween candy — that circulate the way ancient myths and fairy tales once did, but dressed in contemporary settings like cities, cars, and telephones. 'Urban' here marks it as a creature of modern, mobile, mass society rather than old rural folklore, even though the stories themselves travel just as happily through suburbs and small towns.