Old English forgiefnes, forgifennys "pardon, forgiveness, indulgence," from past participle of forgifan (see forgive) + -ness. Contracted from *forgiven-ness. Middle English also had forgift (early 14c.).
forgetful
forget-me-not
forgettable
forgivable
forgive
forgiveness
forgiving
forgo
forgotten
fork
forked