Main Entry: ³arch

Function: adjective

Etymology: ¹arch-

Date: 1547

1 : principal, chief <your arch opponent>
2 a : mischievous, saucy b : marked by a deliberate and often forced playfulness, irony, or impudence <known for her arch comments> <decided to answer them by being teacherly in a sort of arch, Olympian way — Gerald Early>

— arch·ness noun