under the knife

1. 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.

Example Sentences

Gone are the days when facelifts were reserved for the ageing wealthy - now an increasing number of younger people are opting to go under the knife.

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As he finishes, the client, who has been under the knife for four hours, smiles in relief.

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Each time you go under the knife you are rolling the dice.

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She said the partnership with TikTok would help people "make safer and more informed choices before they go under the knife – wherever that may be."

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He was the first to go under the knife.

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