Toggle

A wooden pin tapering toward both ends with a groove around its middle, fixed transversely in the eye of a rope to be secured to any other loop or bight or ring; a kind of button or frog capable of being readily engaged and disengaged for temporary purposes.

Two rods or plates connected by a toggle joint.

any instruction that works first one way and then the other; it turns something on the first time it is used and then turns it off the next time