gas pump vs gasoline pump

gas pump and gasoline pump both are nouns.

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

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

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

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

gas pump (noun)	gasoline 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