GA vs organophosphate nerve agent

GA and organophosphate nerve agent both are nouns.

Word	Noun	Adjective	Verb	Adverb
GA	Yes	No	No	No
organophosphate nerve agent	Yes	No	No	No

As nouns, organophosphate nerve agent is a hypernym of GA; that is, organophosphate nerve agent is a word with a broader meaning than GA:

GA: the first known nerve agent, synthesized by German chemists in 1936; a highly toxic combustible liquid that is soluble in organic solvents and is used as a nerve gas in chemical warfare
organophosphate nerve agent: any of a series of nerve agents containing organophosphate compounds first synthesized by German chemists in 1936; in World War II the Germans tested them in concentration camps but not on the battlefield; Iraq is alleged to have used them against Iran and against the Kurds

Other hypernyms of GA include G-series agent, G-series nerve agent, G agent.

GA (noun)	organophosphate nerve agent (noun)
a state in southeastern United States; one of the Confederate states during the American Civil War	any of a series of nerve agents containing organophosphate compounds first synthesized by German chemists in 1936; in World War II the Germans tested them in concentration camps but not on the battlefield; Iraq is alleged to have used them against Iran and against the Kurds
the first known nerve agent, synthesized by German chemists in 1936; a highly toxic combustible liquid that is soluble in organic solvents and is used as a nerve gas in chemical warfare