pop up vs pop out

pop up and pop out both are verbs.

Word	Noun	Adjective	Verb	Adverb
pop up	No	No	Yes	No
pop out	No	No	Yes	No

As verbs, pop up and pop out are synonyms defined as:

pop up and pop out: appear suddenly or unexpectedly; happen unexpectedly

Other synonyms of pop up include burst out, crop up, pop.

pop up (verb)	pop out (verb)
appear suddenly or unexpectedly; happen unexpectedly	come out suddenly or forcefully
	exit briefly
	bulge outward
	appear suddenly or unexpectedly; happen unexpectedly