n. pl. eight·ies
1. The cardinal number equal to 8 × 10.
a. A decade or the numbers from 80 to 89: They were still active in their eighties. Before noon, the temperature shot into the eighties.
b. often Eighties The decade from 80 to 89 in a century.
[Middle English eighti, from Old English eahtatig; see oktō(u) in the Appendix of Indo-European roots.]
eighty adj. & pron.
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