portraiture vs portrait

portraiture and portrait both are nouns.

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

As nouns, portraiture and portrait are synonyms defined as:

portraiture and portrait: a word picture of a person's appearance and character

Other synonyms of portraiture include portrayal.

portraiture (noun)	portrait (noun)
the activity of making portraits	any likeness of a person, in any medium
a word picture of a person's appearance and character	a word picture of a person's appearance and character