A bolt designed for attachment to the bottom of a door. Usually the bolt is controlled by a trigger, which holds the bolt against a spring. Release of the trigger permits the spring to move the bolt into the unlocked position.
(n.) A bolt mechanism typically mounted at the bottom of a door, and designed to be easily operated by ones foot. Source: Lock Industry Standards and Training (LIST) Council
A type of bolt applied at the bottom of a door and arranged for foot operation. Generally the bolt head is held up by a spring when the door is unbolted.