circuit n1 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
: the court of appeals for a circuit in the federal judicial system [after the 9th Circuit 's ruling "V. M. Sher"]
Source: Merriam-Webster's Dictionary of Law ©1996. Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Incorporated.