terribly | sense examples, Usage and Definition from wordnet dictionary online

Adverbial terribly has 2 senses

terribly, awfully, awful, frightfully - used as intensifiers; "terribly interesting"; "I'm awful sorry"
terribly, atrociously, awfully, abominably, abysmally, rottenly - in a terrible manner; "she sings terribly"
Derived from adjective terrible₂