mindmap
root((陡的))
steep
implies such sharpness of pitch that ascent or descent is difficult: a ~ staircase leading to the attic.
abrupt
implies a sharper pitch and a sudden break in the level: a beach with an ~ drop-off.
precipitous
applies to steepness approaching the vertical: the airplane went into a ~ nosedive.
sheer
suggests an unbroken perpendicular expanse: climbers able to ascend ~ cliffs.