dec·ade (dĕkād′, dĕ-kād)
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 dek in the Appendix of Indo-European roots.]
deca·dal (dĕkə-dəl) adj.
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