defining moment

American  

noun

1. a point at which the essential nature or character of a person, group, etc., is revealed or identified.

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Etymology

Origin of defining moment

First recorded in 1980–85

Example Sentences

“Today marks the next phase of the Arm compute platform and a defining moment for our company.”

From Barron's • Mar. 24, 2026

Kaja Kallas, who leads the European Commission’s foreign and security policy, described the killing of Khamenei as “a defining moment in Iran’s history.”

From The Wall Street Journal • Mar. 1, 2026

Father James Martin: This was a defining moment for me.

From Slate • Feb. 21, 2026

The strike “would be a defining moment in the history of the coalfields,” Giardina said, “and Jackson made it clear where he stood.”

From Salon • Feb. 19, 2026

This was the defining moment in the correspondence.

From "Founding Brothers: The Revolutionary Generation" by Joseph J. Ellis