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

See Examples For:

knife edge

Local campaigners believe the by-election is on a knife edge, not least thanks to Restore Britain, a relatively new party led by former Reform UK MP Rupert Lowe.

From BBC ● Jun. 11, 2026

With two games left, the relegation fight between Tottenham and West Ham is on a knife edge - and their recent form tells two very different stories.

From BBC ● May 12, 2026

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

At the moment, the House rests on a knife edge with 219 Republicans and 212 Democrats.

From BBC ● Aug. 5, 2025

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

From "1491" by Charles C. Mann

Related Words

• pleat