annoyance vs bummer

annoyance and bummer both are nouns.

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

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

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

annoyance (noun)	bummer (noun)
the act of troubling or annoying someone	an experience that is irritating or frustrating or disappointing
something or someone that causes trouble; a source of unhappiness	a bad reaction to a hallucinogenic drug
anger produced by some annoying irritation
an unpleasant person who is annoying or exasperating
the psychological state of being irritated or annoyed