1.
culmination; crowning achievement; comprehensive compilation
A work or achievement that brings together and represents the best of accumulated efforts, knowledge, or experience. Often used for a definitive work or the peak of someone's career.
Usage
集大成 carries a sense of bringing together everything that has been accumulated over a long period. It is always positive — implying something definitive and impressive.
Unlike English "magnum opus" which focuses on a single greatest work, 集大成 emphasizes the process of gathering and synthesizing accumulated experience or knowledge into a final, comprehensive result.