characterise vs characterisation

characterise is not a noun while characterisation is a noun.

Word	Noun	Adjective	Verb	Adverb
characterise	No	No	Yes	No
characterisation	Yes	No	No	No

characterise (noun)	characterisation (noun)
	a graphic or vivid verbal description
	the act of describing distinctive characteristics or essential features

characterise (verb)	characterisation (verb)
describe or portray the character or the qualities or peculiarities of
be characteristic of