promo vs promotion

promo and promotion both are nouns.

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

As nouns, promo and promotion are synonyms defined as:

promo and promotion: a message issued in behalf of some product or cause or idea or person or institution

Other synonyms of promo include packaging, promotional material, publicity.

promo (noun)	promotion (noun)
a message issued in behalf of some product or cause or idea or person or institution	act of raising in rank or position
	the advancement of some enterprise
	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