The definition of a decade is a period of 10 years.(noun)
An example of decade is 1990 to 2000.
See decade in Webster's New World College Dictionary
Origin: LME < OFr < LL decas (gen. decadis) < Gr dekas < deka, ten
See decade in American Heritage Dictionary 4
Origin: Middle English, a group of ten
Origin: , from Old French
Origin: , from Late Latin decas, decad-
Origin: , from Greek dekas
Origin: , from deka, ten; see dekm̥ in Indo-European roots.
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