vertical stabiliser vs tail fin

vertical stabiliser and tail fin both are nouns.

Word	Noun	Adjective	Verb	Adverb
vertical stabiliser	Yes	No	No	No
tail fin	Yes	No	No	No

As nouns, vertical stabiliser and tail fin are synonyms defined as:

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

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

vertical stabiliser (noun)	tail fin (noun)
a stabilizer that is part of the vertical tail structure of an airplane	the tail of fishes and some other aquatic vertebrates
	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