The Collaborative International Dictionary of English v.0.48:

Circuit \Cir"cuit\, n. [F. circuit, fr. L. circuitus, fr.
   circuire or circumire to go around; circum around + ire to
   go.]
   1. The act of moving or revolving around, or as in a circle
      or orbit; a revolution; as, the periodical circuit of the
      earth round the sun. --Watts.
      [1913 Webster]

   2. The circumference of, or distance round, any space; the
      measure of a line round an area.
      [1913 Webster]

            The circuit or compass of Ireland is 1,800 miles.
                                                  --J. Stow.
      [1913 Webster]

   3. That which encircles anything, as a ring or crown.
      [1913 Webster]

            The golden circuit on my head.        --Shak.
      [1913 Webster]

   4. The space inclosed within a circle, or within limits.
      [1913 Webster]

            A circuit wide inclosed with goodliest trees.
                                                  --Milton.
      [1913 Webster]

   5. A regular or appointed journeying from place to place in
      the exercise of one's calling, as of a judge, or a
      preacher.
      [1913 Webster]

   6.
      (a) (Law) A certain division of a state or country,
          established by law for a judge or judges to visit, for
          the administration of justice. --Bouvier.
      (b) (Methodist Church) A district in which an itinerant
          preacher labors.
          [1913 Webster]

   7. Circumlocution. [Obs.] "Thou hast used no circuit of
      words." --Huloet.
      [1913 Webster]

   Circuit court (Law), a court which sits successively in
      different places in its circuit (see Circuit, 6). In the
      United States, the federal circuit courts are commonly
      presided over by a judge of the supreme court, or a
      special circuit judge, together with the judge of the
      district court. They have jurisdiction within statutory
      limits, both in law and equity, in matters of federal
      cognizance. Some of the individual States also have
      circuit courts, which have general statutory jurisdiction
      of the same class, in matters of State cognizance.

   Circuit of action or Circuity of action (Law), a longer
      course of proceedings than is necessary to attain the
      object in view.

   To make a circuit, to go around; to go a roundabout way.

   Voltaic circle or Galvanic circle or Voltaic circuit or
   Galvanic circuit, a continous electrical communication
      between the two poles of a battery; an arrangement of
      voltaic elements or couples with proper conductors, by
      which a continuous current of electricity is established.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Circuit \Cir"cuit\, v. i.
   To move in a circle; to go round; to circulate. [Obs.] --J.
   Philips.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Circuit \Cir"cuit\, v. t.
   To travel around. [Obs.] "Having circuited the air." --T.
   Warton.
   [1913 Webster]

WordNet (r) 3.0 (2006):

circuit
    n 1: an electrical device that provides a path for electrical
         current to flow [syn: circuit, electrical circuit,
         electric circuit]
    2: a journey or route all the way around a particular place 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" [syn: tour, circuit]
    3: an established itinerary of venues or events that a
       particular group of people travel 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: the boundary line 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" [syn:
       circumference, circuit]
    5: (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 particular circuit
       court of appeals
    6: a racetrack for automobile races [syn: racing circuit,
       circuit]
    7: movement once around a course; "he drove an extra lap just
       for insurance" [syn: lap, circle, circuit]
    v 1: make a circuit; "They were circuiting about the state"

Moby Thesaurus II by Grady Ward, 1.0:

238 Moby Thesaurus words for "circuit":
   O, air lane, alentours, ambages, ambience, ambit,
   amplifier circuit, annular muscle, annulus, arena, areola, arsis,
   association, astable circuit, aureole,
   back-to-back switching circuit, bailiwick, beat, booking, border,
   borderland, borderlands, borscht circuit, bound, boundary, bout,
   break, broken circuit, bypass, campaign, chaplet, circle,
   circuital field, circuiteer, circuitry, circulate, circulation,
   circumambiencies, circumambulate, circumbendibus, circumference,
   circumjacencies, circummigrate, circumnavigate, circumstances,
   circumvent, circumvolution, circus, close the circle,
   closed circle, closed circuit, coast-to-coast hookup,
   come full circle, compass, complete circuit, conference, confines,
   context, corona, coronet, coupling circuit, course, crown, cycle,
   date, dead circuit, demesne, department, describe a circle, detour,
   deviation, diadem, diastole, digression, discus, disk, domain,
   dominion, downbeat, edge, encircle, encompass, engagement,
   entourage, environing circumstances, environment, environs,
   equivalent circuit, eternal return, excursion, expedition,
   fairy ring, field, flank, flight path, flip-flop circuit,
   full circle, galvanic circuit, garland, gestalt, girdle,
   girdle the globe, girth, glory, go about, go around, go round,
   go the round, grand tour, gyration, gyre, habitat, halo,
   hemisphere, hookup, hot circuit, itinerary, jaunt, journey,
   judicial circuit, junket, jurisdiction, lap, lasso,
   lateral circuit, leg, limit, line, live circuit, logical circle,
   loop, looplet, magic circle, magnetic circuit, make a circuit,
   march, margin, microcircuit, milieu, monostable circuit,
   multiple circuit, multiple series, neighborhood, net, network,
   nonsinusoidal circuit, noose, orb, orbit, outing, outline,
   outposts, outskirts, package tour, pale, path, peregrination,
   perimeter, periphery, pilgrimage, playing engagement,
   pleasure trip, precinct, precincts, primrose path, printed circuit,
   progress, province, pulse, purlieus, radio links, radius, realm,
   rectifier circuit, revolution, revolve, ring, road, rondelle,
   rotation, round, round trip, roundabout, roundabout way, roundel,
   rounds, route, rubberneck tour, run, safari, sally, saucer,
   sea lane, semiconductor circuit, series, series multiple, shoot,
   short, short circuit, shortcut, situation, skirt, spell, sphere,
   sphincter, spiral, stalk, stand, suburbs, surround, surroundings,
   systole, thermionic tube circuit, thesis, total environment, tour,
   track, trade route, traject, trajectory, trajet,
   transistor circuit, travels, trek, trip, turn, upbeat,
   vaudeville circuit, vector field, vicinage, vicinity,
   vicious circle, voyage, walk, way, wheel, whirl, wreath



The Free On-line Dictionary of Computing (30 December 2018):

circuit

   1.  A communications path in a circuit
   switching network.

   2.  A complete path through which an electric
   current can flow.

   The term is used loosely for any device or subsystem using
   electrical or electronic components.  E.g. "That lightning
   bolt fried the circuits in my GPS receiver".  An integrated
   circuit (IC) contains components built on a Silicon die.

   (2002-07-15)


Easton's 1897 Bible Dictionary:

Circuit
   the apparent diurnal revolution of the sun round the earth (Ps.
   19:6), and the changes of the wind (Eccl. 1:6). In Job 22:14,
   "in the circuit of heaven" (R.V. marg., "on the vault of
   heaven") means the "arch of heaven," which seems to be bent over
   our heads.