adj. 25B6; adjective
steep cliffs : PRECIPITOUS, sheer, abrupt, sharp, perpendicular, vertical, bluff, vertiginous.
a steep increase : SHARP, sudden, precipitate, precipitous, rapid.
(informal) steep prices : EXPENSIVE, dear, costly, high, stiff; unreasonable, excessive, exorbitant, extortionate, outrageous, prohibitive; Brit. over the odds.
gentle, gradual, reasonable.