murderer Meaning, Definition & Usage

  1. noun a criminal who commits homicide (who performs the unlawful premeditated killing of another human being)
    manslayer; liquidator.

WordNet

Mur"der*er noun
Definitions
  1. One guilty of murder; a person who, in possession of his reason, unlawfully kills a human being with premeditated malice.
  2. A small cannon, formerly used for clearing a ship's decks of boarders; -- called also murdering piece. Obs.

Webster 1913