knife edge

American  

noun

1. the cutting edge of a knife.

2. anything very sharp.

3. a wedge on the fine edge of which a scale beam, pendulum, or the like, balances or oscillates.

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knife edge British  

noun

1. the sharp cutting edge of a knife

2. any sharp edge

3. a sharp-edged wedge of hard material on which the beam of a balance pivots or about which a pendulum is suspended

4. a critical point in the development of a situation, process of making a decision, etc

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Etymology

Origin of knife edge

First recorded in 1810–20

Example Sentences

Nevertheless, investors should watch Bitcoin through the long weekend with the Middle East situation on a knife edge and market-moving news all but inevitable.

From Barron's • Apr. 3, 2026

"Ultimately the best team generally wins Test matches but this one, it's on a bit more of a knife edge of conditions."

From BBC • Nov. 28, 2025

"I've never played a golf course as hard. Every shot is on a knife edge."

From BBC • Jun. 12, 2025

"We're on a knife edge, we've got weeks, otherwise it's going to cost us a large chunk for no reason," Mr Gorton said.

From BBC • Mar. 5, 2025

Thus the tropical forest, despite its fabulous vitality, exists on a knife edge.

From "1491" by Charles C. Mann

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