cir·cuit n
1 a: a route formerly taken by traveling judges
b: a district established within a state or the federal judicial system see also the judicial system in the back matter
2 cap: the court of appeals for a circuit in the federal judicial system
after the 9th Circuit 's ruling — V. M. Sher
Merriam-Webster’s Dictionary of Law. Merriam-Webster. 1996.