This idiom expresses extreme confidence that something will not happen, with the speaker metaphorically wagering they’ll ‘eat their hat’ if proven wrong. It’s used to dismiss a possibility as absurd or to challenge others’ predictions, often with a bold, humorous, or defiant tone. The phrase is applied in casual or argumentative contexts, reflecting certainty or skepticism, and its exaggerated imagery adds a playful or theatrical flair to debates or assertions.

The phrase likely emerged in 19th-century Britain, tied to the cultural significance of hats as personal items, making the idea of eating one absurd. An early use appears in Charles Dickens’ *The Pickwick Papers* (1837): ‘If I knew as little of life as that, I’d eat my hat.’ The idiom gained traction in Victorian England, reflecting a love for colorful expressions, and was popularized in American English by the late 19th century, as seen in Mark Twain’s journalism. Its use in vaudeville and early cinema further spread it, cementing its place as a humorous way to express disbelief across English-speaking cultures.