• Piston Definition & Synonyms
- (n.) A sliding piece which either is moved by, or moves against, fluid pressure. It usually consists of a short cylinder fitting within a cylindrical vessel along which it moves, back and forth. It is used in steam engines to receive motion from the steam, and in pumps to transmit motion to a fluid; also for other purposes.
• Piston ring Definition & Synonyms
- () A spring packing ring, or any of several such rings, for a piston.