knuckle under

phrasal verb·1 sense·particle under

Usefulness

Meanings

1

Submit to authority or pressure

Pressureuncommon

Why “under”? A person or thing loses strength under pressure, weight, or demands.

“He refused to knuckle under to threats.”
He refused to give in to threats from above.
“Maya would not knuckle under to pressure from the board.”
Maya would not give in to pressure from the board.

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buckle under

Same under pattern: pressure

Yield or break under strain; Give in to pressure to do something

cave under

Same under pattern: pressure

Collapse beneath weight or pressure

sink under

Same under pattern: pressure

Drop below the surface, often metaphorically

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