1851, from flat (adj.), which was used from late 14c. of plates, dishes, saucers in a sense "shallow; smooth-surfaced" + ware (n.). Originally as distinguished from hollow ware; U.S. sense of "domestic cutlery" recorded by 1895.
flattery
flat-top
flatulence
flatulent
flatus
flatware
flaunt
flautist
Flavian
Flavius
flavor