hold on vs obstinate

hold on is not an adjective while obstinate is an adjective.

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

As verbs, obstinate is a hyponym of hold on; that is, obstinate is a word with a more specific, narrower meaning than hold on:

Other hyponyms of hold on include ask for it, ask for trouble, plug, plug away, follow, stick to, stick with.

hold on (adjective)	obstinate (adjective)
	tenaciously unwilling or marked by tenacious unwillingness to yield
	resistant to guidance or discipline
	stubbornly persistent in wrongdoing

hold on (verb)	obstinate (verb)
be persistent, refuse to stop	persist stubbornly
stop and wait, as if awaiting further instructions or developments
hold the phone line open
hold firmly
retain possession of