The Collaborative International Dictionary of English v.0.48:
Koellia \Koellia\ n. (Bot.) The genus comprising the American mountain mint, synonymous with Pycnanthemum. Syn: Pycnanthemum, genus Pycnanthemum, genus Koellia. [WordNet 1.5 +PJC]WordNet (r) 3.0 (2006):
Koellia n 1: American mountain mint [syn: Pycnanthemum, genus Pycnanthemum, Koellia, genus Koellia]