Or'i·ganO*rig'a*num noun [ Latin origanum , Greek ..., ..., probably from 'o`ros , mountain + ... brightness, beauty. Confer Organy .] (Botany) A genus of aromatic labiate plants, including the sweet marjoram ( O. Marjorana ) and the wild marjoram... Found on http://www.encyclo.co.uk/webster/O/32