late 14c. (early 14c. as a surname), "a maker, a smith," agent noun from forge (v.). Meaning "a counterfeiter, one who makes by false imitation" is from early 15c. In 15c. also "a maker of (coin) money." Another Middle English word for "a forger" was falsarie (mid-15c.).
forfeiture
forfend
forgat
forgave
forge
forger
forgery
forget
forgetful
forget-me-not
forgettable