switch

Universal Words noun, verb noun 1 a small device that you press or move up and down in order to turn a light or piece of electrical equipment on and off: a light switch * an on-off switch * That was in the days before electricity was available at the flick of a switch. * Which switch do I press to turn it off? * to throw a switch (= to move a large switch) 2 ~ (in / of sth)