Reciprocating engines also known as the piston-cylinder device has proven to be very versatile having a wide range of applications. Engineering devices and instruments like automobiles, trucks, aircraft, ships and electrical power generators integrates such application. Sketch and describe/explain the nomenclature and terminology used in reciprocating engines application. 1. Top dead center 2. Bottom dead center 3. Stroke 4. Bore 5. Intake valve 6. Exhaust valve 7. Clearance volume 8. Displacement volume 9. Compression ratio 10. Mean effective pressure