invigilate vs keep an eye on

invigilate and keep an eye on both are verbs.

Word	Noun	Adjective	Verb	Adverb
invigilate	No	No	Yes	No
keep an eye on	No	No	Yes	No

As verbs, keep an eye on is a hypernym of invigilate; that is, keep an eye on is a word with a broader meaning than invigilate:

Other hypernyms of invigilate include follow, observe, watch, watch over.

invigilate (verb)	keep an eye on (verb)
watch over (students taking an exam, to prevent cheating)	follow with the eyes or the mind