５０年代ごじゅうねんだい

noun

the '50s; the fifties

Refers to a decade, typically the 1950s, but can be any century's 50s depending on context.

• 彼かれは５０年ねん代だいの音おん楽がくが大だい好すきだ。

  He loves music from the '50s.

• この建たて物ものは１９５０年ねん代だいに建たてられた。

  This building was built in the 1950s.