irritate vs fret

irritate is not a noun while fret is a noun.

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

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

Other hyponyms of irritate include chafe, gall, itch, rub, scratch.

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

irritate (noun)	fret (noun)
	a small bar of metal across the fingerboard of a musical instrument; when the string is stopped by a finger at the metal bar it will produce a note of the desired pitch
	an ornamental pattern consisting of repeated vertical and horizontal lines (often in relief)
	a spot that has been worn away by abrasion or erosion
	agitation resulting from active worry

irritate (verb)	fret (verb)
excite to an abnormal condition, or chafe or inflame	wear away or erode
excite to some characteristic action or condition, such as motion, contraction, or nervous impulse, by the application of a stimulus	remove soil or rock
cause annoyance in; disturb, especially by minor irritations	cause friction
	be too tight; rub or press
	decorate with an interlaced design
	carve a pattern into
	be agitated or irritated
	cause annoyance in
	gnaw into; make resentful or angry
	worry unnecessarily or excessively
	become or make sore by or as if by rubbing
	provide (a musical instrument) with frets