erect vs get up

erect is an adjective but get up is not an adjective.

Word	Noun	Adjective	Verb	Adverb
erect	No	Yes	Yes	No
get up	No	No	Yes	No

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

Other hypernyms of erect include bring up, elevate, lift, raise.

erect (adjective)	get up (adjective)
upright in position or posture
of sexual organs; stiff and rigid

erect (verb)	get up (verb)
construct, build, or erect	get up and out of bed
cause to rise up	cause to rise
	put on special clothes to appear particularly appealing and attractive
	develop
	study intensively, as before an exam
	arrange by systematic planning and united effort
	raise from a lower to a higher position
	rise to one's feet