pissed off vs irritated

pissed off and irritated both are adjectives.

Word	Noun	Adjective	Verb	Adverb
pissed off	No	Yes	No	No
irritated	No	Yes	No	No

As adjectives, pissed off and irritated are synonyms defined as:

Other synonyms of pissed off include annoyed, miffed, nettled, peeved, pissed, riled, roiled, steamed, stung.

pissed off (adjective)	irritated (adjective)
aroused to impatience or anger	aroused to impatience or anger