gasoline pump vs gas pump

gasoline pump and gas pump both are nouns.

Word	Noun	Adjective	Verb	Adverb
gasoline pump	Yes	No	No	No
gas pump	Yes	No	No	No

As nouns, gasoline pump and gas pump are synonyms defined as:

gasoline pump and gas pump: a pump in a service station that draws gasoline from underground storage tanks

Other synonyms of gasoline pump include island dispenser, petrol pump.

gasoline pump (noun)	gas pump (noun)
a pump in a service station that draws gasoline from underground storage tanks	a pump in a service station that draws gasoline from underground storage tanks