portrayal vs characterisation

portrayal and characterisation both are nouns.

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

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

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

portrayal (noun)	characterisation (noun)
representation by drawing or painting etc	a graphic or vivid verbal description
acting the part of a character on stage; dramatically representing the character by speech and action and gesture	the act of describing distinctive characteristics or essential features
any likeness of a person, in any medium
a representation by picture or portraiture
a word picture of a person's appearance and character