Definition of top dead center (tdc) in English English dictionary
(Otomotiv) The point at which the piston has reached the top of its stroke and has compressed the fuel/air mixture to the greatest extent. BTDC and ATCD mean before and after top dead center. These terms are used to refer to timing marks
A position in the four-stroke combustion process wherein the piston is at the topmost point in its stroke. This can either be during the compression phase or the combustion phase