expression
steep slope; sudden drop; precipitous incline
Describes a road, path, or terrain that drops or rises sharply. Often used literally, but can appear in figurative contexts for a sudden decline.
この先は急な坂になっているので、自転車は押して歩いてください。
There's a steep slope ahead, so please dismount and walk your bicycle.
山道には急な坂がいくつもあった。
There were many steep slopes on the mountain trail.