piston ring(redirected from piston rings)
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Related to piston rings: connecting rod
An adjustable split metal ring that fits around a piston and seals the gap between the piston and the cylinder wall.
(Automotive Engineering) a split ring, usually made of cast iron, that fits into a groove on the rim of a piston to provide a spring-loaded seal against the cylinder wall
a metal ring, split so it can expand, placed around a piston to ensure a tight fit in the cylinder of an engine.