nark

(noun) an informer or spy working for the police. Synonyms: copper's nark.

(noun) a lawman concerned with narcotics violations. Synonyms: narc, narcotics agent.

(verb) cause annoyance in; disturb, especially by minor irritations. Synonyms: annoy, rag, get to, bother, get at, irritate, rile, nettle, gravel, vex, chafe, devil. Examples: "Mosquitoes buzzing in my ear really bothers me." "It irritates me that she never closes the door after she leaves."

(verb) inform or spy (for the police).