'fling off' definitions:

Definition of 'fling off'

From: WordNet
verb
Write quickly; "She dashed off a note to her husband saying she would not be home for supper"; "He scratched off a thank-you note to the hostess" [syn: dash off, scratch off, knock off, toss off, fling off]

Synonyms of 'fling off'

From: Moby Thesaurus