오랜 시간 동안 물이나 바람에 깎여 표면이 매끄럽게 다듬어진 아주 커다란 바위.
A very large, typically rounded rock that has been shaped and smoothed by erosion or the action of water and weather.
예문:
"The mountain stream flowed around massive boulders that had fallen from the cliffs above."
"We sat on a sun-warmed boulder to eat our lunch while looking out over the valley."
"Glaciers are capable of transporting heavy boulders over hundreds of miles."