A sloping surface; an inclined plane such as the side of a hill or a bevel.
登山道の斜面は急で注意が必要だ。
The slope of the trail is steep and requires caution.
雪で斜面が滑りやすくなっている。
The slope has become slippery because of the snow.
建物の屋根は斜面になっていることが多い。
Roofs of buildings are often sloped.