■ prime: 7. a period of power, vigour, etc., usually following youth (esp in the phrase the prime of life)
■ 4. [N-UNCOUNT] usu poss N △If someone or something is in their prime, they are at the stage in their existence when they are at their strongest, most active, or most successful.
- She was in her intellectual prime...
- We've had a series of athletes trying to come back well past their prime.
- ...young persons in the prime of life.
- She's now forty and still in her prime.
- He is now past his prime.
- a man in the prime of life
- a young singer who was tragically cut off in her prime (=died while she was in her prime)