a rod that tilts about a pivot to produce a useful movement. Levers lift or move loads. Example: Shovel, nutcracker, seesaw, crowbar, elbow, tweezers, bottle opener

The traditional method by which a mortice lock is operated; 5, 3 or 2 lever mechanisms. The cutting on the key raises the levers until they form a horizontal plane. The deadbolt can then be thrown into the locked position.

Levers are components in locks not operated by a cylinder, which lock in place the bolt or latch. Generally, the higher the number of levers, the more secure the lock. Typically, interior doors have two or three lever locks and exterior door locks are fitted with five to seven levers.

The levers prevent the bolt sliding back and forward. They provide the security from being 'picked' and the more levers there are, the more complex the key is, and the more secure the lock is.