See flare in Webster's New World Roget's A-Z Thesaurus II
verb
To undergo combustion:
blaze1, burn, combust, flame. See hotTo become manifest suddenly and in full force.
Also used with up: break out, burst (forth or out), erupt, explode. See explosion, startTo react explosively or suddenly.
Also used with up: fly. See explosion
phrasal verb flare upTo be or become angry:
anger, blow up, boil over, bristle, burn, explode, foam, fume, rage, seethe. (Informal) steam. Idioms: blow a fuse, blow a gasket, blow one's stack (or top), breathe fire, fly off the handle, get hot under the collar, hit the ceiling (or roof), lose one's temper, see red. See feelings
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