circuit

circuit — noun

1. a complete path that electricity flows through, made of wires and electronic par

1.nounC2
Definition

a complete path that electricity flows through, made of wires and electronic parts; or a system of pipes through which a liquid or gas flows in a closed loop.

Example

A short circuit in the kitchen caused the lights to go out.

collocation: short circuit

The electrician checked every circuit in the apartment for loose wires.

Common collocations
  • electrical circuit
  • short circuit
  • closed circuit
  • circuit board
  • printed circuit
  • break a circuit
  • circuit breaker
Synonyms
  • wiring

    refers to the physical wires, not the complete path they form

  • loop

    can describe a closed path but is less precise in electrical contexts

Usage Note

The most common sense in everyday language. 'Short circuit' is a fixed compound noun meaning an unintended connection that stops the normal flow. 'Closed circuit' describes a system where the same material (water, refrigerant) circulates repeatedly.

Common Mistakes

The electricity stopped because the flow broke.
The electricity stopped because the circuit was broken.
'circuit' names the path; a break in the path stops the current.
I need to fix the current in this lamp.
I need to fix the circuit in this lamp.
'current' is the flow moving through the 'circuit' (the path).

2. a path, route, or track that forms a closed loop, returning to its starting poin

2.nounC2
Definition

a path, route, or track that forms a closed loop, returning to its starting point — used for racing, walking, or driving around a particular area.

Example

The running circuit around the lake is exactly two kilometers long.

collocation: running circuit

Race cars reached speeds of three hundred kilometers per hour on the tight racing circuit.

collocation: racing circuit

Common collocations
  • racing circuit
  • running circuit
  • complete a circuit
  • circuit of the park
  • walking circuit
  • scenic circuit
Synonyms
  • track

    focuses on the surface used for racing; 'circuit' emphasizes the closed-loop shape

  • loop

    a simpler word for any curved path returning to its start; less technical than 'circuit'

  • course

    the general path or direction of movement, not necessarily closed

Usage Note

Distinguish from sense 3 (SERIES OF VISITS): this sense refers to a physical path or track, not a schedule of events. A 'circuit' in this sense can be measured in distance (kilometers, laps).

Common Mistakes

She ran one circle around the park.
She ran one circuit around the park.
'circuit' is the standard noun for a complete loop; 'circle' is the geometric shape.
The motorcycle track was a closed loop of two miles.
The motorcycle circuit was a closed loop of two miles.
'circuit' is preferred for racing tracks.

3. a set of stops at different places that a performer, speaker, or athlete attends

3.nounC2
Definition

a set of stops at different places that a performer, speaker, or athlete attends in a regular order, moving from one location to the next — for instance, a comedian appearing at clubs nationwide, or a tennis player competing in tournaments internationally.

Example

The comedian spent two years on the club circuit before anyone noticed him.

collocation: on the [noun] circuit

After winning the award, the director joined the international film-festival circuit.

Common collocations
  • on the circuit
  • circuit of clubs
  • professional circuit
  • lecture circuit
  • festival circuit
Synonyms
  • tour

    focuses on the journey itself; 'circuit' implies a repeated or regular schedule of stops

  • itinerary

    more formal and refers to a planned travel schedule, not necessarily repeated

  • rotation

    suggests a fixed repeating cycle of places or people

Grammar Patterns

circuit + of + noun phrase

Usage Note

Often follows the preposition 'on' (e.g. 'on the comedy circuit', 'on the lecture circuit'). The noun before 'circuit' usually names the type of event or profession.

Common Mistakes

She joined the round of fashion shows.
She joined the fashion-show circuit.
'circuit' implies a regular series, not just one round.
He works on the circle of music festivals.
He works on the music-festival circuit.
'circuit', not 'circle', is the correct noun for a series of connected events.

4. a geographic area or district that a judge travels to in order to hear legal cas

4.nounC2
Definition

a geographic area or district that a judge travels to in order to hear legal cases in different courts; also the group of courts within that area.

Example

Judge Okafor presides over the ninth judicial circuit, covering five rural counties.

collocation: judicial circuit

The lawyer has practiced law in this circuit for over twenty years.

Common collocations
  • judicial circuit
  • circuit court
  • federal circuit
  • circuit judge
  • within the circuit
Synonyms
  • district

    a geographic division but without the historical sense of a traveling judge

  • jurisdiction

    the legal authority of a court, not necessarily tied to a traveling route

Usage Note

Used almost exclusively in legal contexts. In the United States, the federal court system is divided into numbered 'circuits' (e.g. the Ninth Circuit), each with a court of appeals.

Common Mistakes

The criminal was tried in the city circuit.
The criminal was tried in the circuit court for that district.
'circuit' alone is not a place; it describes the court system or area.
The judge made a circuit around the courtroom.
The judge presides over a circuit of several counties.
'circuit' in law means an area, not a physical lap.

circuit — verb

Word family

  • circuitry
    nounC2
  • circuitous
    adjectiveC2
  • circuitously
    adverbC2
  • circuital
    adjectiveC2

Synonym discussion

Sense: noun/3

These five words all describe a path of movement, but differ in shape and purpose. A 'circuit' is a closed loop that returns to its starting point, used especially for racing or regular routes — the cars completed three circuits of the race track. A 'track' is the physical surface or lane itself, which may or may not be circular: joggers use the school track for practice. A 'loop' emphasizes a curved or circular shape but is often shorter and less formal: the walking trail forms a simple loop through the woods. A 'course' is the general direction or route of movement, not necessarily closed — the golf course has eighteen holes spread across a large area. A 'lap' specifically means one complete trip around a circuit or track: the runner finished the first lap in sixty seconds. In racing contexts, 'circuit' names the whole track, while 'lap' counts the trips around it.

circuit ↗track ↗loopcourse ↗lap ↗

Common collocations

Adverbs

  • around + circuit

Prepositions

  • on a circuit
  • around a circuit
  • through a circuit

Etymology

LatinFrenchEnglish

The word 'circuit' comes from Latin 'circuitus', meaning 'a going around', formed from 'circum' (around) and 'ire' (to go). It entered English through Old French 'circuit' in the 14th century, first used for a journey that returns to the start. The electrical meaning appeared in the 18th century when scientists began describing the complete path of an electric current.