point of view vs viewpoint

point of view and viewpoint both are nouns.

Word	Noun	Adjective	Verb	Adverb
point of view	Yes	No	No	No
viewpoint	Yes	No	No	No

As nouns, point of view and viewpoint are synonyms defined as:

point of view and viewpoint: a mental position from which things are viewed

Other synonyms of point of view include stand, standpoint.

point of view (noun)	viewpoint (noun)
the spatial property of the position from which something is observed	a mental position from which things are viewed
a mental position from which things are viewed	a place from which something can be viewed