respond vs rejoin

respond and rejoin both are verbs.

Word	Noun	Adjective	Verb	Adverb
respond	No	No	Yes	No
rejoin	No	No	Yes	No

As verbs, rejoin is a hyponym of respond; that is, rejoin is a word with a more specific, narrower meaning than respond:

Other hyponyms of respond include call back, counter, field, sass, come back, repay, retort, return, riposte, bridle.

respond (verb)	rejoin (verb)
show a response or a reaction to something	answer back
respond favorably or as hoped	join again
react verbally