noun
: any of various elementary mechanisms having the elements of which all machines are composed and including the lever, the wheel and axle, the pulley, the inclined plane, the wedge, and the screw
noun
: any of various elementary mechanisms having the elements of which all machines are composed and including the lever, the wheel and axle, the pulley, the inclined plane, the wedge, and the screw
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012