noun
1. : a reciprocating valve consisting of a piston or connected pistons working in a cylindrical case provided with ports that are traversed by the valve
2. : piston 2a
noun
1. : a reciprocating valve consisting of a piston or connected pistons working in a cylindrical case provided with ports that are traversed by the valve
2. : piston 2a
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012