Webster’s Revised Unabridged Dictionary · 1913
Decade
Dec′ade (dĕk′ād), n. [F. décade, L. decas, -adis, fr. Gr. δεκάς, fr. δέκα ten. See Ten.] A group or division of ten; esp., a period of ten years; a decennium; as, a decade of years or days; a decade of soldiers; the second decade of Livy. [Written also decad.]
During this notable decade of years. Gladstone.