wall painting vs painting

wall painting and painting both are nouns.

Word	Noun	Adjective	Verb	Adverb
wall painting	Yes	No	No	No
painting	Yes	No	No	No

As nouns, painting is a hypernym of wall painting; that is, painting is a word with a broader meaning than wall painting:

wall painting: a painting that is applied to a wall surface
painting: graphic art consisting of an artistic composition made by applying paints to a surface

Other hypernyms of wall painting include picture.

wall painting (noun)	painting (noun)
a painting that is applied to a wall surface	creating a picture with paints
	the occupation of a house painter
	the act of applying paint to a surface
	graphic art consisting of an artistic composition made by applying paints to a surface