dress up vs decorate

dress up and decorate both are verbs.

Word	Noun	Adjective	Verb	Adverb
dress up	No	No	Yes	No
decorate	No	No	Yes	No

As verbs, decorate is a hypernym of dress up; that is, decorate is a word with a broader meaning than dress up:

Other hypernyms of dress up include adorn, beautify, embellish, grace, ornament.

dress up (verb)	decorate (verb)
put on special clothes to appear particularly appealing and attractive	provide with decoration
dress in a costume	make more attractive by adding ornament, colour, etc.
dress in a certain manner	award a mark of honor, such as a medal, to
make something appear superficially attractive	be beautiful to look at
put a caparison on