Definition of power stroke in English:

power stroke

noun

  • The stage of the cycle of an internal combustion engine in which the piston is driven outward by the expansion of gases.

    • ‘Deactivation requires only 40 or so milliseconds and is timed to occur immediately after the power stroke so the disabled cylinder remains filled with exhaust gas.’
    • ‘The result is that a portion of the following power stroke is wasted, trying to burn already deoxygenated exhaust.’
    • ‘We really only want the top ring to seal against the cylinder wall primarily on the power stroke; on the other three strokes, it's just along for the ride.’