think up vs create mentally

think up and create mentally both are verbs.

Word	Noun	Adjective	Verb	Adverb
think up	No	No	Yes	No
create mentally	No	No	Yes	No

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

think up: devise or invent
create mentally: create mentally and abstractly rather than with one's hands

Other hypernyms of think up include create by mental act.

think up (verb)	create mentally (verb)
devise or invent	create mentally and abstractly rather than with one's hands