'Terribly' definitions:

Definition of 'terribly'

From: WordNet
adverb
Used as intensifiers; "terribly interesting"; "I'm awful sorry" [syn: terribly, awfully, awful, frightfully]
adverb
In a terrible manner; "she sings terribly" [syn: terribly, atrociously, awfully, abominably, abysmally, rottenly]

Definition of 'Terribly'

From: GCIDE
  • Terrible \Ter"ri*ble\, a. [F., fr. L. terribilis, fr. terrere to frighten. See Terror.]
  • 1. Adapted or likely to excite terror, awe, or dread; dreadful; formidable. [1913 Webster]
  • Prudent in peace, and terrible in war. --Prior. [1913 Webster]
  • Thou shalt not be affrighted at them; for the Lord thy God is among you, a mighty God and terrible. --Deut. vii. 21. [1913 Webster]
  • 2. Excessive; extreme; severe. [Colloq.] [1913 Webster]
  • The terrible coldness of the season. --Clarendon. [1913 Webster]
  • Syn: Terrific; fearful; frightful; formidable; dreadful; horrible; shocking; awful. [1913 Webster] -- {Ter"ri*ble*ness}, n. -- {Ter"ri*bly}, adv. [1913 Webster]

Synonyms of 'terribly'

From: Moby Thesaurus