Definition of narcs:
(n) :
(informal, colloquial, drugs) A police officer or federal agent assigned to or engaging in illegal narcotics control.
(n) :
(colloquial, informal) A narcissist.
(v) :
(underwater diving, slang) To suffer from impaired judgment due to nitrogen narcosis (for example, while scuba diving).
(n) :
(informal, colloquial) Alternative spelling of nark (“spy”). [(UK, Ireland) A police spy or informer.]
(v) :
(informal, colloquial) Alternative spelling of nark. [(transitive, intransitive, slang) To serve or behave as a spy or informer; to tattle.]