[1] : The Collaborative International Dictionary of English v.0.48

concurrent \concur"rent\, n.
   1. one who, or that which, concurs; a joint or contributory
      cause.
      1913 webster

            to all affairs of importance there are three
            necessary concurrents . . . time, industry, and
            faculties.                            --dr. h. more.
      1913 webster

   2. one pursuing the same course, or seeking the same objects;
      hence, a rival; an opponent.
      1913 webster

            menander . . . had no concurrent in his time that
            came near unto him.                   --holland.
      1913 webster

   3. chron. one of the supernumerary days of the year over
      fifty-two complete weeks; -- so called because they concur
      with the solar cycle, the course of which they follow.
      1913 webster

[2] : The Collaborative International Dictionary of English v.0.48

concurrent \concur"rent\, a. f. concurrent, l. concurrens, p.
   pr. of concurrere.
   1. acting in conjunction; agreeing in the same act or
      opinion; contributing to the same event or effect;
      cooperating.
      1913 webster

            i join with these laws the personal presence of the
            kings' son, as a concurrent cause of this
            reformation.                          --sir j.
                                                  davies.
      1913 webster

            the concurrent testimony of antiquity. --bp.
                                                  warburton.
      1913 webster

   2. conjoined; associate; concomitant; existing or happening
      at the same time.
      1913 webster

            there is no difference the concurrent echo and the
            iterant but the quickness or slowness of the return.
                                                  --bacon.
      1913 webster

            changes . . . concurrent with the visual changes in
            the eye.                              --tyndall.
      1913 webster

   3. joint and equal in authority; taking cognizance of similar
      questions; operating on the same objects; as, the
      concurrent jurisdiction of courts.
      1913 webster

   4. geom. meeting in one point.

   syn: meeting; uniting; accompanying; conjoined; associated;
        coincident; united.
        1913 webster

[3] : WordNet (r) 2.0

concurrent
     adj : occurring or operating at the same time; "a series of
           coincident events" syn: coincident, coincidental,
           coinciding, cooccurring, simultaneous
see also:
coincident coincidental coinciding cooccurring simultaneous 

[4] : Moby Thesaurus II by Grady Ward, 1.0

142 moby thesaurus words for "concurrent":
   accessory, accompanying, accordant, agreeing, aligned, analogous,
   approaching, associate, associated, asymptotic, at one,
   at one with, attendant, attending, carried by acclamation,
   centripetal, centrolineal, coacting, coactive, coadjutant,
   coadjuvant, coadunate, coefficient, coetaneous, coeternal, coeval,
   coexistent, coexisting, coextending, coextensive, coincident,
   coinstantaneous, collaborative, collateral, collective,
   collectivist, collectivistic, collusive, combined, combining,
   commensal, common, communal, communalist, communalistic, communist,
   communistic, communitarian, compact, comprehensive, concerted,
   concomitant, concordant, concurring, confluent, confocal, conjoint,
   conjugate, conjunct, connivent, conniving, consentaneous,
   consilient, conspiratorial, contemporaneous, contemporary,
   conterminous, converging, cooperant, cooperating, cooperative,
   coordinate, corporate, correlative, coterminous, coupled,
   coworking, ecumenic, equal, equidistant, equispaced, even, fellow,
   focal, harmonious, harmonized, in agreement, inclusive, isochronal,
   isochronous, joined, joint, like-minded, lined up, meeting, mutual,
   mutually approaching, noncompetitive, nonconvergent, nondivergent,
   of a piece, of one accord, of one mind, paired, parallel,
   parallelepipedal, parallelinervate, paralleling, parallelodrome,
   parallelogrammatic, parallelogrammic, parallelotropic, parasitic,
   radial, radiating, reciprocal, saprophytic, simultaneous, solid,
   symbiotic, synchronal, synchronic, synchronous, synergetic,
   synergic, synergistic, tangent, tangential, twin, unanimous,
   unchallenged, uncompetitive, uncontested, uncontradicted,
   uncontroverted, unison, unisonous, united, uniting, unopposed,
   with one consent, with one voice

[5] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

concurrent. running together; having the same authority; thus we say a 
concurrent consideration occurs in the case of mutual promises; such and 
such a court have concurrent jurisdiction; that is, each has the same 
jurisdiction. 

Concurrent >> C Words
Concurrent, definition of term: Concurrent
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