基本解釋[材料科學(xué)]頂置氣門發(fā)動機[機械工程]頂置氣門發(fā)動機英英字典柯林斯英英字典 a type of internal-combustion engine in which the inlet and exhaust valves are in the cylinder head above the pistons (US name valve-in-head engine)&rarrcompareside-valve engine overhead-valve engine劍橋字典overhead-valve engine柯林斯字典專業(yè)釋義材料科學(xué)頂置氣門發(fā)動機機械工程頂置氣門發(fā)動機