Definition of spark plug gap in English English dictionary
(Otomotiv) The space between the center and side spark plug electrodes, across which the spark must jump to ignite the fuel/air mixture in the combustion chamber. Adjusting this gap is a major part of the basic tune-up, because the width of the gap affects the intensity of the spark
The space filled with air or other dielectric between high potential terminals (as of an electrostatic machine, induction coil, or condenser), through which the discharge passes; the air gap of a jump spark