'GD' definitions:

Definition of 'GD'

From: WordNet
noun
A nerve agent easily absorbed into the body; a lethal cholinesterase inhibitor that is highly toxic when inhaled [syn: soman, GD]
noun
A ductile silvery-white ductile ferromagnetic trivalent metallic element of the rare earth group [syn: gadolinium, Gd, atomic number 64]