'Detestably' definitions:

Definition of 'detestably'

(from WordNet)
adverb
In an offensive and hateful manner; "I don't know anyone who could have behaved so abominably" [syn: detestably, repulsively, abominably, odiously]

Definition of 'Detestably'

From: GCIDE
  • Detestably \De*test"a*bly\, adv. In a detestable manner. [1913 Webster]