hassle vs irritate

hassle is a noun but irritate is not a noun.

Word	Noun	Adjective	Verb	Adverb
hassle	Yes	No	Yes	No
irritate	No	No	Yes	No

As verbs, irritate is a hypernym of hassle; that is, irritate is a word with a broader meaning than hassle:

Other hypernyms of hassle include annoy, bother, chafe, devil, get at, get to, gravel, nark, nettle, rag, rile, vex.

hassle (noun)	irritate (noun)
disorderly fighting
an angry disturbance

hassle (verb)	irritate (verb)
annoy continually or chronically	excite to an abnormal condition, or chafe or inflame
	excite to some characteristic action or condition, such as motion, contraction, or nervous impulse, by the application of a stimulus
	cause annoyance in; disturb, especially by minor irritations