'Steeply' definitions:

Definition of 'steeply'

(from WordNet)
adverb
In a steep manner; "the street rose steeply up to the castle"

Definition of 'Steeply'

From: GCIDE
  • Steeply \Steep"ly\ (st[=e]p"l[y^]), adv. In a steep manner; with steepness; with precipitous declivity. [1913 Webster]