harbour vs hold on

harbour is a noun but hold on is not a noun.

Word	Noun	Adjective	Verb	Adverb
harbour	Yes	No	Yes	No
hold on	No	No	Yes	No

As verbs, hold on is a hypernym of harbour; that is, hold on is a word with a broader meaning than harbour:

Other hypernyms of harbour include keep.

harbour (noun)	hold on (noun)
a place of refuge and comfort and security
a sheltered port where ships can take on or discharge cargo

harbour (verb)	hold on (verb)
maintain (a theory, thoughts, or feelings)	be persistent, refuse to stop
hold back a thought or feeling about	stop and wait, as if awaiting further instructions or developments
keep in one's possession; of animals	hold the phone line open
secretly shelter (as of fugitives or criminals)	hold firmly
	retain possession of