a. rare–1. [f. L. trīgintā thirty + -enni-um (f. ann-us year) + -AL.]. Taking place once in thirty years.
1894. Yale News (New Haven, Conn.), 29 June. About twenty-five members of the class were present at their trigintennial reunion.
a. rare–1. [f. L. trīgintā thirty + -enni-um (f. ann-us year) + -AL.]. Taking place once in thirty years.
1894. Yale News (New Haven, Conn.), 29 June. About twenty-five members of the class were present at their trigintennial reunion.
