blinker (Noun) — A light that flashes on and off; used as a signal or to send messages.
blinker (Noun) — A blinking light on a motor vehicle that indicates the direction in which the vehicle is about to turn.
blinker (Noun) — Blind consisting of a leather eyepatch sewn to the side of the halter that prevents a horse from seeing something on either side.
blinker (Verb) — Put blinders on (a horse).