burst forth vs blossom

burst forth is not a noun while blossom is a noun.

Word	Noun	Adjective	Verb	Adverb
burst forth	No	No	Yes	No
blossom	Yes	No	Yes	No

As verbs, blossom is a hypernym of burst forth; that is, blossom is a word with a broader meaning than burst forth:

Other hypernyms of burst forth include bloom, flower.

burst forth (noun)	blossom (noun)
	reproductive organ of angiosperm plants especially one having showy or colorful parts
	the period of greatest prosperity or productivity

burst forth (verb)	blossom (verb)
be unleashed; emerge with violence or noise	develop or come to a promising stage
come into or as if into flower	produce or yield flowers
jump out from a hiding place and surprise (someone)