vigintennial

a. 每20年一次的

释义与例句

adj.
  1. 1.

    Synonym of vicennial, occurring every twenty years.

    罕用

词源

From viginti- (“twenty”) + -ennial (“yearly”), from Latin vīgintī (“twenty”) and -enniālis, from annus (“year”) + -is (“forming compound adjectives”) + -ālis (“-al: forming adjectives”).

来源：wiktionary