build up vs re-arm

build up and re-arm both are verbs.

Word	Noun	Adjective	Verb	Adverb
build up	No	No	Yes	No
re-arm	No	No	Yes	No

As verbs, re-arm is a hyponym of build up; that is, re-arm is a word with a more specific, narrower meaning than build up:

Other hyponyms of build up include rearm, forearm.

build up (verb)	re-arm (verb)
form or accumulate steadily	arm anew
enlarge, develop, or increase by degrees or in stages
change the use of and make available or usable
bolster or strengthen
prepare oneself for a military confrontation