irradiate vs bombard

irradiate is not a noun while bombard is a noun.

Word	Noun	Adjective	Verb	Adverb
irradiate	No	No	Yes	No
bombard	Yes	No	Yes	No

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

irradiate (noun)	bombard (noun)
	a large shawm; the bass member of the shawm family

irradiate (verb)	bombard (verb)
expose to radiation	direct high energy particles or radiation against
cast rays of light upon	address with continuously or persistently, as if with a barrage
give spiritual insight to; in religion	throw bombs at or attack with bombs
	cast, hurl, or throw repeatedly with some missile