glass jaw

American  

noun

1. a person's jaw, especially that of a boxer, that is vulnerable to even a light blow.

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glass jaw British  

noun

1. informal boxing a jaw that is excessively fragile or susceptible to punches

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Etymology

Origin of glass jaw

First recorded in 1910–15

Example Sentences

They might have class, but they also have a glass jaw.

From BBC • May 6, 2022

But for now it’s the other way around — and the Yankees seem to have a glass jaw.

From New York Times • Jun. 27, 2021

This way, Cline hit a series of targets at once: a new emotional window onto the banality of evil; an homage to a literary hero; and a squarely landed blow across the bogeyman’s glass jaw.

From Los Angeles Times • Sep. 1, 2020

"America's 'Iron Lady' does not have a glass jaw," Hart told the Journal.

From US News • May 5, 2015

It's too bad he's got a glass jaw.

From The Valley of the Moon by London, Jack