mustard gas vs sulfur mustard

mustard gas and sulfur mustard both are nouns.

Word	Noun	Adjective	Verb	Adverb
mustard gas	Yes	No	No	No
sulfur mustard	Yes	No	No	No

As nouns, mustard gas and sulfur mustard are synonyms defined as:

mustard gas and sulfur mustard: a toxic war gas with sulfide based compounds that raises blisters and attacks the eyes and lungs; there is no known antidote

Other synonyms of mustard gas include blistering agent, dichloroethyl sulfide, mustard agent.

mustard gas (noun)	sulfur mustard (noun)
a toxic war gas with sulfide based compounds that raises blisters and attacks the eyes and lungs; there is no known antidote	a toxic war gas with sulfide based compounds that raises blisters and attacks the eyes and lungs; there is no known antidote