vertical stabiliser vs vertical stabilizer

vertical stabiliser and vertical stabilizer both are nouns.

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

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

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

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

vertical stabiliser (noun)	vertical stabilizer (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