invent vs think up

invent and think up both are verbs.

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

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

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

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