buildup vs promotion

buildup and promotion both are nouns.

Word	Noun	Adjective	Verb	Adverb
buildup	Yes	No	No	No
promotion	Yes	No	No	No

As nouns, promotion is a hypernym of buildup; that is, promotion is a word with a broader meaning than buildup:

buildup: highly favorable publicity and praise
promotion: a message issued in behalf of some product or cause or idea or person or institution

Other hypernyms of buildup include packaging, promo, promotional material, publicity.

buildup (noun)	promotion (noun)
the act of building up an accumulation	act of raising in rank or position
highly favorable publicity and praise	the advancement of some enterprise
the result of the process of accumulation	a message issued in behalf of some product or cause or idea or person or institution
	encouragement of the progress or growth or acceptance of something