decadal


dec·ade

D0065400 (dĕk′ād′, dĕ-kād′)n.1. A period of ten years.2. A group or series of ten.
[Middle English, a group of ten, from Old French, from Late Latin decas, decad-, from Greek dekas, from deka, ten; see dekm̥ in Indo-European roots.]
dec′a·dal (dĕk′ə-dəl) adj.