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3. under the knife

under the knife

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under the knife

having a medical operation I wouldn't go under the knife just to improve my appearance.

Usage notes: most often used with the verbs go or be, as in the example

See also: knife

under the knife

Undergoing surgery, as in He was awake the entire time he was under the knife. The phrase is often put as go under the knife meaning "be operated on," as in When do you go under the knife? Knife standing for "surgery" was first recorded in 1880.

See also: knife

under the knife

Informal

Undergoing surgery.

See also: knife