grapheme vs graph

grapheme and graph both are nouns.

Word	Noun	Adjective	Verb	Adverb
grapheme	Yes	No	No	No
graph	Yes	No	Yes	No

As nouns, grapheme and graph are synonyms defined as:

Other synonyms of grapheme include character, graphic symbol.

grapheme (noun)	graph (noun)
a written symbol that is used to represent speech	a visual representation of the relations between certain quantities, represented as points, plotted with reference to a set of axes
	a visual display of information
	a written symbol that is used to represent speech

grapheme (verb)	graph (verb)
	represent by means of a graph
	plot upon a graph