under the knife

Idioms  

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.

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Example Sentences

See Examples For:

under the knife

Yes, this horrendous TV egg could only have hatched in a place like Hollywood, where mother-daughter spa days might also mean going under the knife.

From Salon ● Oct. 1, 2026

But Standard Oil finally went under the knife in 1911, split into 34 separate companies that sometimes seem like they are bent on reunifying.

From Barron's ● May 2, 2026

Patients who went under the knife late last year are now debuting tighter skin, flatter stomachs and lifted eyelids to their social networks.

From The Wall Street Journal ● Feb. 7, 2026

The case managers said partners pushed surgeries and would give bonuses when clients went under the knife.

From Los Angeles Times ● Dec. 31, 2025

He was effusively thankful to the doctors for not insisting he be put under the knife.

From "Endgame" by Frank Brady