The decade of one's life from age 80 through age 89.(noun)
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Use "eighties" in a sentence
"One reason so many good horror writer went to seed in the eighties is they kept trying to do and say the same thing in the same way."
"Anyone who came through the eighties is also used to the idea that from time to time a pea-brain can take charge of the White House and make his country do very silly things."
"I think an important feature of the eighties is the growing preeminence of government-to-government relationships in international economic decision-making."