tall tale

noun

Etymology: From tall (“exaggerated”) + tale.

1. A tale or story which is fantastic and greatly exaggerated; also, an account of questionable veracity; a lie, an untruth.

   “He returned on Monday with a tall tale about a 100-pound fish he had caught.”

   “The head-in-sand idea is a threadbare, 2,000-year-old hand-me-down from the Roman naturalist Pliny, who sometimes passed on tall tales.”