ˈad.əˌraksē noun
also at·a·rax·ia ˌ ̷ ̷ ̷ ̷ˈraksēə
( plural ataraxies also ataraxias )
Etymology: Middle French & Greek; Middle French ataraxie, from Greek ataraxia, from ataraktos undisturbed (from a- a- (II) + taraktos, verbal of tarattein, tarassein to disturb, stir) + -ia -y — more at dreg
: calmness untroubled by mental or emotional disquiet : intellectual detachment : imperturbability