栏杆的英语单词是 "railing"，来源于古英语的 "regn" 或 "regnian"，意为 "to rule" 或 "to keep in order"。栏杆通常用于保护人们不掉下台阶或防止物品掉落。例如：

The railing along the stairs is loose and needs to be fixed.（楼梯旁的栏杆松动了，需要修理。）

I grabbed onto the railing to keep from falling.（我抓住栏杆以防摔倒。）

The railing around the balcony prevents children from climbing over.（阳台四周的栏杆防止孩子爬过去。）