n.
Function: adjective
Etymology: 1 arch-
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