the '80s; the eighties
Refers to the decade of the 1980s. Can be used for any century, but typically means the 1980s.
I like music from the 80s.
This movie is set in the 80s.
Kanji numeral spelling; less common than ８０年代 but still seen.
Compound of ８０ (eighty) and 年代 (era, decade).