hold on vs store

hold on is not a noun while store is a noun.

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

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

hold on (noun)	store (noun)
	a mercantile establishment for the retail sale of goods or services
	a depository for goods
	an electronic memory device
	a supply of something available for future use

hold on (verb)	store (verb)
be persistent, refuse to stop	keep or lay aside for future use
stop and wait, as if awaiting further instructions or developments	find a place for and put away for storage
hold the phone line open
hold firmly
retain possession of