The story
Introduced by Gerard 't Hooft in the 1978 paper On the phase transition towards permanent quark confinement.
Etymology from Wiktionary, CC BY-SA 4.0.
't Hooft operator
Today it means: A dual version of the Wilson loop in which the electromagnetic potential A is replaced by its electromagnetic dual Aᵐᵃᵍ, where the exterior derivative of A is equal to the Hodge dual of the exterior derivative of Aᵐᵃᵍ. Full definition →