D defs.my
Entry 2 senses Webster, 1913

Decennary

· De·cen·na·ry · IPA /dɪˈsɛnəɹi/
01 n. A period of ten years.
pl. Decennaries ((#))
  1. 1.
    A period of ten years.
  2. 2.
    A tithing consisting of ten neighboring families.(O. Eng. Law)