1. (noun)circuit, electrical circuit, electric circuit an electrical device that provides a path for electrical current to flow
2. (noun)tour, circuit a journey or route all the way around a particularplace or area "they took an extended tour of Europe"; "we took a quick circuit of the park"; "a ten-day coach circuit of the island"
3. (noun)circuit an established itinerary of venues or events that a particulargroup of peopletravel to
"she's a familiar name on the club circuit"; "on the lecture circuit"; "the judge makes a circuit of the courts in his district"; "the international tennis circuit"
4. (noun)circumference, circuit the boundaryline encompassing an area or object "he had walked the full circumference of his land"; "a danger to all races over the whole circumference of the globe"
5. (noun)circuit (law) a judicial division of a state or the United States (so-called because originally judges traveled and held court in different locations); one of the twelve groups of states in the United States that is covered by a particularcircuitcourt of appeals