The Collaborative International Dictionary of English v.0.48:

Aggregate \Ag"gre*gate\, n.
   1. A mass, assemblage, or sum of particulars; as, a house is
      an aggregate of stone, brick, timber, etc.
      [1913 Webster]

   Note: In an aggregate the particulars are less intimately
         mixed than in a compound.
         [1913 Webster]

   2. (Physics) A mass formed by the union of homogeneous
      particles; -- in distinction from a compound, formed by
      the union of heterogeneous particles.
      [1913 Webster]

   In the aggregate, collectively; together.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Aggregate \Ag"gre*gate\, v. t. [imp. & p. p. Aggregated; p.
   pr. & vb. n. Aggregating.] [L. aggregatus, p. p. of
   aggregare to lead to a flock or herd; ad + gregare to collect
   into a flock, grex flock, herd. See Gregarious.]
   1. To bring together; to collect into a mass or sum. "The
      aggregated soil." --Milton.
      [1913 Webster]

   2. To add or unite, as, a person, to an association.
      [1913 Webster]

            It is many times hard to discern to which of the two
            sorts, the good or the bad, a man ought to be
            aggregated.                           --Wollaston.
      [1913 Webster]

   3. To amount in the aggregate to; as, ten loads, aggregating
      five hundred bushels. [Colloq.]
      [1913 Webster]

   Syn: To heap up; accumulate; pile; collect.
        [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Aggregate \Ag"gre*gate\, a. [L. aggregatus, p. p.]
   1. Formed by a collection of particulars into a whole mass or
      sum; collective.
      [1913 Webster]

            The aggregate testimony of many hundreds. --Sir T.
                                                  Browne.
      [1913 Webster]

   2. (Anat.) Formed into clusters or groups of lobules; as,
      aggregate glands.
      [1913 Webster]

   3. (Bot.) Composed of several florets within a common
      involucre, as in the daisy; or of several carpels formed
      from one flower, as in the raspberry.
      [1913 Webster]

   4. (Min. & Geol.) Having the several component parts adherent
      to each other only to such a degree as to be separable by
      mechanical means.
      [1913 Webster]

   5. (Zool.) United into a common organized mass; -- said of
      certain compound animals.
      [1913 Webster]

   Corporation aggregate. (Law) See under Corporation.
      [1913 Webster]

WordNet (r) 3.0 (2006):

aggregate
    adj 1: formed of separate units gathered into a mass or whole;
           "aggregate expenses include expenses of all divisions
           combined for the entire year"; "the aggregated amount of
           indebtedness" [syn: aggregate, aggregated,
           aggregative, mass]
    2: composed of a dense cluster of separate units such as carpels
       or florets or drupelets; "raspberries are aggregate fruits"
    n 1: the whole amount [syn: sum, total, totality,
         aggregate]
    2: material such as sand or gravel used with cement and water to
       make concrete, mortar, or plaster
    3: a sum total of many heterogenous things taken together [syn:
       aggregate, congeries, conglomeration]
    v 1: amount in the aggregate to
    2: gather in a mass, sum, or whole [syn: aggregate, combine]

Moby Thesaurus II by Grady Ward, 1.0:

175 Moby Thesaurus words for "aggregate":
   A to Z, A to izzard, account, accumulate, accumulated,
   accumulation, acervation, add up, add up to, agglomerate,
   agglomeration, aggregate to, aggregation, aggroup, all,
   all and sundry, all-embracing, all-inclusive, alpha and omega,
   amass, amassed, amassment, amount, amount to, assemblage, assemble,
   assembled, batch, be-all, be-all and end-all, beginning and end,
   box score, bring together, budget, bulk, bunch, bunch together,
   bunch up, bunched, bundled, cast, chunk, clump, clumped, cluster,
   clustered, collect, collected, colligate, collocate, combine,
   combined, come, come to, compare, compile, complement,
   comprehensive, comprise, congeries, conglobation, conglomerate,
   conglomeration, congregate, congregated, contain, corral, count,
   cumulate, cumulation, difference, dig up, draw together, dredge up,
   drive together, each and every, entire, entirety, everything,
   exhaustive, fascicled, fasciculated, gather, gather in,
   gather together, gathered, gathering, get in, get together,
   glomerate, glomeration, gob, gross, group, heaped, holistic, hunk,
   in session, inclusive, integral, integrated, join, joined, joint,
   juxtapose, knotted, leagued, length and breadth, lump,
   lump together, lumped, make up, mass, massed, match, meeting,
   mobilize, mount up to, muster, number, omnibus, one, one and all,
   one and indivisible, package, package deal, packaged, pair,
   partner, piled, product, put together, quantity, quantum, raise,
   rake up, rally, reckon up to, reckoning, round up, run into,
   run to, score, scrape together, set, snowball, stacked, stockpile,
   sum, sum total, summation, take up, tale, tally, the bottom line,
   the corpus, the ensemble, the entirety, the lot, the story,
   the whole, the whole range, the whole story, tot up to, total,
   totality, tote, tote up to, unitize, universal, wad, whip in,
   whole, wrapped up, x number



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

AGGREGATE. A collection of particular persons or items, formed into one
body; as a corporation aggregate, which is one formed of a number of natural
persons; the union of individual charges make an aggregate charge.