Entry 2 senses · 2 variants Webster, 1913 Tetradynamian · Tet·ra·dy·na·mi·an · IPA n. a. 01 n. A plant of the order Tetradynamia. 1. A plant of the order Tetradynamia.(Bot.) 02 a. Belonging to the order Tetradynamia; having six stamens, four of which are uniformly longer than the others. 1. Belonging to the order Tetradynamia; having six stamens, four of which are uniformly longer than the others.(Bot.)