The Collaborative International Dictionary of English v.0.48:

Circulate \Cir"cu*late\, v. i. [imp. & p. p. Circulated; p.
   pr. & vb. n. Circulating.] [L. circulatus, p. p. of
   circulare, v. t., to surround, make round, circulari, v. i.,
   to gather into a circle. See Circle.]
   [1913 Webster]
   1. To move in a circle or circuitously; to move round and
      return to the same point; as, the blood circulates in the
      body. --Boyle.
      [1913 Webster]

   2. To pass from place to place, from person to person, or
      from hand to hand; to be diffused; as, money circulates; a
      story circulates.
      [1913 Webster]

   Circulating decimal. See Decimal.

   Circulating library, a library whose books are loaned to
      the public, usually at certain fixed rates.

   Circulating medium. See Medium.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Circulate \Cir"cu*late\, v. t.
   To cause to pass from place to place, or from person to
   person; to spread; as, to circulate a report; to circulate
   bills of credit.
   [1913 Webster]

   Circulating pump. See under Pump.

   Syn: To spread; diffuse; propagate; disseminate.
        [1913 Webster]

WordNet (r) 3.0 (2006):

circulate
    v 1: become widely known and passed on; "the rumor spread"; "the
         story went around in the office" [syn: go around,
         spread, circulate]
    2: cause to become widely known; "spread information";
       "circulate a rumor"; "broadcast the news" [syn: circulate,
       circularize, circularise, distribute, disseminate,
       propagate, broadcast, spread, diffuse, disperse,
       pass around]
    3: cause be distributed; "This letter is being circulated among
       the faculty" [syn: circulate, pass around, pass on,
       distribute]
    4: move through a space, circuit or system, returning to the
       starting point; "Blood circulates in my veins"; "The air here
       does not circulate"
    5: move in circles [syn: circle, circulate]
    6: cause to move in a circuit or system; "The fan circulates the
       air in the room"
    7: move around freely; "She circulates among royalty"
    8: cause to move around; "circulate a rumor" [syn: mobilize,
       mobilise, circulate]

Moby Thesaurus II by Grady Ward, 1.0:

119 Moby Thesaurus words for "circulate":
   advertise, air, announce, become public, break, bring out,
   broadcast, bruit about, buzz about, circle, circuit, circuiteer,
   circumambulate, circummigrate, circumnavigate, circumrotate,
   circumvent, circumvolute, close the circle, come across with,
   come forth, come full circle, come out, compass, course, crank,
   cycle, deliver, deliver over, demonetize, describe a circle,
   devaluate, devalue, disseminate, distribute, divulge, encircle,
   encompass, find vent, flank, flow, fly about, fork over, forward,
   get about, get abroad, get afloat, get around, get exposure,
   girdle, girdle the globe, give in, give out, give over, go about,
   go around, go forth, go round, go the round, go the rounds, gyrate,
   gyre, hand, hand in, hand out, hand over, have currency, issue,
   lap, make a circuit, make known, noise abroad, orbit, pass,
   pass out, pass over, pirouette, pivot, proclaim, promulgate,
   publicize, publish, put about, put out, reach, reissue, remonetize,
   render, report, resign, revalue, reveal, revolve, rotate, round,
   run, screw, see the light, skirt, spin, spiral, spread,
   spread about, spread like wildfire, surrender, surround, swing,
   swivel, transfer, turn, turn a pirouette, turn around, turn over,
   turn round, twist, utter, wamble, wheel, wind