invent vs dream up

invent and dream up both are verbs.

Word	Noun	Adjective	Verb	Adverb
invent	No	No	Yes	No
dream up	No	No	Yes	No

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

Other hypernyms of invent include concoct, hatch, think of, think up.

invent (verb)	dream up (verb)
come up with (an idea, plan, explanation, theory, or principle) after a mental effort	devise or invent
concoct something artificial or untrue