Oil ring definitions

Oil ring

1) Piston adjunct
Found on https://www.crosswordclues.com/clue/oil-ring

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Oil ring

a loose ring, the inner surface of which rides a shaft or journal and dips into a reservoir of lubricant from which it carries the lubricant to the top of a bearing by its rotation with the shaft.
Found on http://www.encyclo.co.uk/local/21121

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