irritation vs bummer

irritation and bummer both are nouns.

Word	Noun	Adjective	Verb	Adverb
irritation	Yes	No	No	No
bummer	Yes	No	No	No

As nouns, bummer is a hyponym of irritation; that is, bummer is a word with a more specific, narrower meaning than irritation:

Other hyponyms of irritation include huff, miff, seeing red, pinprick, impatience, restlessness, snit.

irritation (noun)	bummer (noun)
unfriendly behavior that causes anger or resentment	an experience that is irritating or frustrating or disappointing
the act of troubling or annoying someone	a bad reaction to a hallucinogenic drug
an uncomfortable feeling of mental painfulness or distress
a sudden outburst of anger
the psychological state of being irritated or annoyed
the neural or electrical arousal of an organ or muscle or gland
(pathology) abnormal sensitivity to stimulation