terribly

/หˆtษ›ษน.ษช.bli/
adverb
  1. 1

    So as to cause terror or awe.

    โ€œThe lion roared terribly.โ€

  2. 2

    Very; extremely.

    โ€œHe's terribly busy and you really shouldn't bother him.โ€

  3. 3

    Very badly.

    โ€œShe took part in the karaoke, but sang terribly.โ€

Source: https://en.wiktionary.org/wiki/terribly