annoyance vs mental state

annoyance and mental state both are nouns.

Word	Noun	Adjective	Verb	Adverb
annoyance	Yes	No	No	No
mental state	Yes	No	No	No

As nouns, mental state is a hypernym of annoyance; that is, mental state is a word with a broader meaning than annoyance:

annoyance: the psychological state of being irritated or annoyed
mental state: (psychology) a mental condition in which the qualities of a state are relatively constant even though the state itself may be dynamic

Other hypernyms of annoyance include mental condition, psychological condition, psychological state.

annoyance (noun)	mental state (noun)
the act of troubling or annoying someone	(psychology) a mental condition in which the qualities of a state are relatively constant even though the state itself may be dynamic
something or someone that causes trouble; a source of unhappiness
anger produced by some annoying irritation
an unpleasant person who is annoying or exasperating
the psychological state of being irritated or annoyed