knob/nɑb/复数形式knobs1旋钮, 按钮a circular rounded projection or protuberanceCopy同义词： boss2把手, 旋钮a small, often rounded, handle that lets one open and close a doorCopy3柄头, 球饰an ornament in the shape of a ball on the hilt of a sword or daggerCopy同义词： pommel4疙瘩, 隆起部分any thickened enlargementCopy同义词： nodethickening