thigh-slapper

American  

[thahy-slap-er] / ˈθaɪˌslæp ər /

noun

Informal.

1. a very funny joke, remark, story, or incident.

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Etymology

Origin of thigh-slapper

First recorded in 1960–65

Example Sentences

The whole thing would be laughable, a real thigh-slapper, if the danger weren’t so real.

From Washington Post

It's an evening full of slapstick and practical jokes – a jolly, enjoyable thigh-slapper of a Shrew – but there's a more unsettling play unable to make itself heard above the uproar.

From The Guardian

So if you’re a Bills fan, Johnson’s stage show was a real thigh-slapper.

From Washington Post