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golden age; prime; heyday; height of prosperity
season (for fruit, vegetables, etc.); best time
昭和初期は日本映画の最盛期だった。
The early Showa period was the golden age of Japanese cinema.
その作家は五十代に最盛期を迎え、多くの傑作を残した。
That author reached the peak of his career in his fifties, leaving behind many masterworks.
バラが最盛期を迎えて庭が色鮮やかになった。
The roses reached their peak bloom and the garden became vivid with color.