1. (noun)soman, GD a nerve agent easily absorbed into the body; a lethal cholinesterase inhibitor that is highly toxic when inhaled Synonyms: soman, atomic number 64, gadolinium
2. (noun)gadolinium, Gd, atomic number 64 a ductile silvery-white ductile ferromagnetic trivalent metallic element of the rare earth group Synonyms: soman, atomic number 64, gadolinium