vertical stabiliser vs tailfin

vertical stabiliser and tailfin both are nouns.

Word	Noun	Adjective	Verb	Adverb
vertical stabiliser	Yes	No	No	No
tailfin	Yes	No	No	No

As nouns, vertical stabiliser and tailfin are synonyms defined as:

vertical stabiliser and tailfin: a stabilizer that is part of the vertical tail structure of an airplane

Other synonyms of vertical stabiliser include tail fin, vertical fin, vertical stabilizer.

vertical stabiliser (noun)	tailfin (noun)
a stabilizer that is part of the vertical tail structure of an airplane	a stabilizer that is part of the vertical tail structure of an airplane
	one of a pair of decorations projecting above the rear fenders of an automobile