G agent vs nerve gas

G agent and nerve gas both are nouns.

Word	Noun	Adjective	Verb	Adverb
G agent	Yes	No	No	No
nerve gas	Yes	No	No	No

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

G agent: a non-persistent nerve agent discovered and synthesized during or prior to World War II by Dr. Gerhard Schrader.
nerve gas: a toxic gas that is inhaled or absorbed through the skin and has harmful effects on the nervous and respiratory system

Other hypernyms of G agent include nerve agent.

G agent (noun)	nerve gas (noun)
a non-persistent nerve agent discovered and synthesized during or prior to World War II by Dr. Gerhard Schrader.	a toxic gas that is inhaled or absorbed through the skin and has harmful effects on the nervous and respiratory system