- the extinguishing or concealment of all visible lights in a city, military post, etc., usually as a precaution against air raids.
- a period during a massive power failure when the lack of electricity for illumination results in utter darkness except from emergency sources, as candles.
- Theater.
- the extinguishing of all stage lights, as in closing a vaudeville skit or separating the scenes of a play.
- a skit ending in a blackout.
- Pathology.
- temporary loss of consciousness or vision: She suffered a blackout from the blow on the head.
- a period of total memory loss, as one induced by an accident or prolonged alcoholic drinking: The patient cannot account for the bizarre things he did during his blackout.
- a brief, passing lapse of memory: An actor may have an occasional blackout and forget a line or two.
- complete stoppage of a communications medium, as by a strike, catastrophe, electrical storm, etc.: a newspaper blackout;a radio blackout.
- a stoppage, suppression, or obliteration: a news blackout.
- a period during which a special sales offer, fare rate, or other bargain is not available: The airline's discount on fares does not apply during the Christmas week blackout.
- a prohibition that is imposed on the broadcasting of an event and has the purpose of encouraging or ensuring ticket sales.
- the extinguishing or hiding of all artificial light, esp in a city visible to an enemy attack from the air
- a momentary loss of consciousness, vision, or memory
- a temporary electrical power failure or cut
- a temporary loss of sensitivity in a valve following a short strong pulse
- a temporary loss of radio communications between a spacecraft and earth, esp on re-entry into the earth's atmosphere
- the suspension of radio or television broadcasting, as by a strike or for political reasons
- to obliterate or extinguish (lights)
- to create a blackout in (a city etc)
- to lose vision, consciousness, or memory temporarily
- to stop (news, a television programme) from being released or broadcast
