noun
fifties
Refers to the decade of the 1950s, or the age range from 50 to 59. Used in contexts like fashion, music, or describing someone's age.
彼女はフィフティーズのファッションが大好きだ。
She loves fifties fashion.
父はフィフティーズで、もうすぐ定年だ。
My father is in his fifties and will retire soon.