stepladder
noun [ C ] uk/ˈstepˌlæd.ər/ us/ˈstepˌlæd.ɚ/ (UK also steps)
活梯，梯凳
a piece of equipment with steps for climbing up and down that can stand on its own or be folded for carrying
I can't reach the top shelf unless I use a stepladder. 不用梯凳，我够不到书架顶层。