Fawce means: Fawce is a British dialect or archaic slang term meaning cunning, sly, or crafty - describing someone who is devious in a calculating, self-interested way rather than openly aggressive. It carries. The word is mostly archaic or historical; you will only encounter it in old texts, period drama, or school history rather than current teen conversation. There is no real cause for parental concern; it is descriptive vocabulary rather than risky behaviour. As a place or proper-name reference it is purely descriptive.