portraiture vs characterisation

portraiture and characterisation both are nouns.

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

As nouns, characterisation is a hypernym of portraiture; that is, characterisation is a word with a broader meaning than portraiture:

Other hypernyms of portraiture include characterization, delineation, depiction, picture, word-painting, word picture.

portraiture (noun)	characterisation (noun)
the activity of making portraits	a graphic or vivid verbal description
a word picture of a person's appearance and character	the act of describing distinctive characteristics or essential features