demonstrate vs demo

demonstrate is not a noun while demo is a noun.

Word	Noun	Adjective	Verb	Adverb
demonstrate	No	No	Yes	No
demo	Yes	No	Yes	No

As verbs, demonstrate and demo are synonyms defined as:

Other synonyms of demonstrate include exhibit, present, show.

demonstrate (noun)	demo (noun)
	a visual presentation showing how something works

demonstrate (verb)	demo (verb)
establish the validity of something, as by an example, explanation or experiment	give an exhibition of to an interested audience
provide evidence for; stand as proof of; show by one's behavior, attitude, or external attributes
give an exhibition of to an interested audience
march in protest; take part in a demonstration