Wiktionary
defining moments
n. (defining moment English)
Usage examples of "defining moments".
As I say, you define yourself partly in relation to other people, and Bart and College had been there for some of my defining moments.
For the rest of us, Challenger was one of the defining moments of the 1980s.
He had had, on the whole, a successful life, and since he had just made his final confession, he was conscious of it as a whole, a story nearly complete, the defining moments as clear as if they had been painted by a fine artist.
He found a spiritual knife-edge in the poetry of alien places, where extreme situations become inevitable and characters are forced toward life-defining moments.