publicity vs promo

publicity and promo both are nouns.

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

As nouns, publicity and promo are synonyms defined as:

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

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

publicity (noun)	promo (noun)
the quality of being open to public view	a message issued in behalf of some product or cause or idea or person or institution
a message issued in behalf of some product or cause or idea or person or institution