steep, abrupt, precipitous, sheer mean having an incline approaching the perpendicular. steep implies such sharpness of pitch that ascent or descent is very difficult <a steep hill><a steep dive>. abrupt implies a sharper pitch and a sudden break in the level <a beach with an abrupt drop-off>. precipitous applies to an incline approaching the vertical <the river winds through a precipitous gorge>. sheer suggests an unbroken perpendicular expanse <sheer cliffs that daunted the climbers>.