murder

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The killing of another person without justification or excuse, especially the crime of killing a person with malice aforethought or with recklessness manifesting extreme indifference to the value of human life.
• noun An instance of such killing.
• noun Slang Something that is very uncomfortable, difficult, or hazardous.
• noun A flock of crows.
• intransitive verb To kill (another human) in an act of murder.
• intransitive verb To kill brutally or inhumanly.
• intransitive verb To put an end to; destroy.
• intransitive verb To spoil by ineptness; mutilate.
• intransitive verb Slang To defeat decisively; trounce.
• intransitive verb To commit murder.
• idiom (get away with murder) To escape punishment for or detection of an egregiously blameworthy act.
• idiom (murder will out) Secrets or misdeeds will eventually be disclosed.

from The Century Dictionary.

• To kill; slay in or as in battle.
• To kill (a human being) with premeditated malice; kill criminally. See murder, n., 1.
• To kill or slaughter in an inhuman or barbarous manner.
• To destroy; put an end to.
• To abuse or violate grossly; mar by bad execution, pronunciation, representation, etc.: as, to murder the queen's English; the actor murdered the part he had to play.
• Synonyms Slay, Despatch, etc. See kill.
• noun Homicide with malice aforethought; as legally defined, the unlawful killing of a human being, by a person of sound mind, by an act causing death within a year and a day thereafter, with premeditated malice.
• noun Slaughter; destruction.

from the GNU version of the Collaborative International Dictionary of English.

• transitive verb To kill with premediated malice; to kill (a human being) willfully, deliberately, and unlawfully. See murder, n.
• transitive verb To destroy; to put an end to.
• transitive verb To mutilate, spoil, or deform, as if with malice or cruelty; to mangle.
• noun The offense of killing a human being with malice prepense or aforethought, express or implied; intentional and unlawful homicide.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun countable An act of deliberate killing of another human being.
• noun uncountable, law The crime of deliberate killing.
• noun uncountable, law The commission of any act which abets the commission of a crime the commission of which causes the death of a person.
• noun uncountable Something terrible to endure.
• noun countable A group of crows; the collective noun for crows.
• verb To deliberately kill (a person or persons).
• verb transitive (sports, figuratively, colloquial) To defeat decisively.
• verb To botch or mangle
• verb figuratively, colloquial To kick someone's ass or chew someone out (used to express one’s anger at somebody).
• verb figuratively, colloquial, UK to devour, ravish.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun unlawful premeditated killing of a human being by a human being
• verb alter so as to make unrecognizable
• verb kill intentionally and with premeditation