decennal
adjEtymology From Latin decennālis (“decennial”), from decennis (“10-year”) + -ālis (“-al”, adjective-forming suffix), from decem (“ten”) + annus (“year”) + -is (suffix forming compound adjectives). Equivalent to decennium + -al.
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Obsolete Synonym of decennial, of or related to a 10-year period.
- They... appointed Archons, or Decennall Governors, that is, one Prince for ten years.1648, Marchamont Nedham, Plea for the King and Kingdome..., page 26: