a rigid bar pivoted about a fulcrum
"The mechanic used a long metal lever to pry the heavy car door open by pushing down on one end while it pivoted around the hinge."
a simple machine that gives a mechanical advantage when given a fulcrum
"The child used a wooden stick as a lever to lift the heavy rock by pivoting it on a small stone fulcrum."
a flat metal tumbler in a lever lock
"The security expert had to carefully extract each small, flat metal lever from the deadbolt to pick the lock."
A crowbar.
"The heavy rain caused the earth to shift, threatening to undermine the old levee that protects the city from flooding."
A levee.
Rather.
"The lever moved slowly rather than quickly."
A surname.
"The Lever family has lived in that town for several generations."
The word comes from the Old French leveor, meaning "a lifter," which was borrowed from the Latin levātor. This Latin term originally described someone or something that raises things up.