doorstop
/ˈdɔːstɒp/(亦作doorstopper)
noun
1- a fixed or heavy object that keeps a door open or stops it from banging against a wall（防止门关上或撞墙的）制门器。
1.1
- figurative a heavy or bulky object (used especially in reference to a thick book)〈喻〉重物; 笨重的东西（尤指厚书）：
his sixth novel is a thumping 400-page doorstop.
他的第六本小说是一本400页的巨大厚书。