check up on vs observe

check up on and observe both are verbs.

Word	Noun	Adjective	Verb	Adverb
check up on	No	No	Yes	No
observe	No	No	Yes	No

As verbs, observe is a hyponym of check up on; that is, observe is a word with a more specific, narrower meaning than check up on:

Other hyponyms of check up on include follow, keep an eye on, watch, watch over.

check up on (verb)	observe (verb)
examine so as to determine accuracy, quality, or condition	stick to correctly or closely
	make mention of
	watch attentively
	observe with care or pay close attention to
	discover or determine the existence, presence, or fact of by perception with the eyes
	follow with the eyes or the mind
	show respect towards
	behave as expected during of holidays or rites
	conform one's action or practice to