airplane vs aeroplane

airplane and aeroplane both are nouns.

Word	Noun	Adjective	Verb	Adverb
airplane	Yes	No	No	No
aeroplane	Yes	No	No	No

As nouns, airplane and aeroplane are synonyms defined as:

airplane and aeroplane: an aircraft that has a fixed wing and is powered by propellers or jets

Other synonyms of airplane include plane.

airplane (noun)	aeroplane (noun)
an aircraft that has a fixed wing and is powered by propellers or jets	an aircraft that has a fixed wing and is powered by propellers or jets