The Collaborative International Dictionary of English v.0.48:

Share \Share\, n. [OE. share, AS. scearu, scaru, fr. sceran to
   shear, cut. See Shear, v.]
   1. A certain quantity; a portion; a part; a division; as, a
      small share of prudence.
      [1913 Webster]

   2. Especially, the part allotted or belonging to one, of any
      property or interest owned by a number; a portion among
      others; an apportioned lot; an allotment; a dividend. "My
      share of fame." --Dryden.
      [1913 Webster]

   3. Hence, one of a certain number of equal portions into
      which any property or invested capital is divided; as, a
      ship owned in ten shares.
      [1913 Webster]

   4. The pubes; the sharebone. [Obs.] --Holland.
      [1913 Webster]

   To go shares, to partake; to be equally concerned.

   Share and share alike, in equal shares.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Share \Share\, n. [OE. schar, AS. scear; akin to OHG. scaro, G.
   schar, pflugshar, and E. shear, v. See Shear.]
   1. The part (usually an iron or steel plate) of a plow which
      cuts the ground at the bottom of a furrow; a plowshare.
      [1913 Webster]

   2. The part which opens the ground for the reception of the
      seed, in a machine for sowing seed. --Knight.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Share \Share\, v. t. [imp. & p. p. Shared; p. pr. & vb. n.
   Sharing.]
   1. To part among two or more; to distribute in portions; to
      divide.
      [1913 Webster]

            Suppose I share my fortune equally between my
            children and a stranger.              --Swift.
      [1913 Webster]

   2. To partake of, use, or experience, with others; to have a
      portion of; to take and possess in common; as, to share a
      shelter with another.
      [1913 Webster]

            While avarice and rapine share the land. --Milton.
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   3. To cut; to shear; to cleave; to divide. [Obs.]
      [1913 Webster]

            The shared visage hangs on equal sides. --Dryden.
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The Collaborative International Dictionary of English v.0.48:

Share \Share\, v. i.
   To have part; to receive a portion; to partake, enjoy, or
   suffer with others.
   [1913 Webster]

         A right of inheritance gave every one a title to share
         in the goods of his father.              --Locke.
   [1913 Webster]

WordNet (r) 3.0 (2006):

share
    n 1: assets belonging to or due to or contributed by an
         individual person or group; "he wanted his share in cash"
         [syn: share, portion, part, percentage]
    2: any of the equal portions into which the capital stock of a
       corporation is divided and ownership of which is evidenced by
       a stock certificate; "he bought 100 shares of IBM at the
       market price"
    3: the allotment of some amount by dividing something; "death
       gets more than its share of attention from theologians" [syn:
       parcel, portion, share]
    4: the part played by a person in bringing about a result; "I am
       proud of my contribution in advancing the project"; "they all
       did their share of the work" [syn: contribution, part,
       share]
    5: a sharp steel wedge that cuts loose the top layer of soil
       [syn: plowshare, ploughshare, share]
    v 1: have in common; "Our children share a love of music"; "The
         two countries share a long border"
    2: use jointly or in common
    3: have, give, or receive a share of; "We shared the cake" [syn:
       partake, share, partake in]
    4: give out as one's portion or share [syn: share, divvy up,
       portion out, apportion, deal]
    5: communicate; "I'd like to share this idea with you"

Moby Thesaurus II by Grady Ward, 1.0:

171 Moby Thesaurus words for "share":
   adjunct, allocate, allocation, allot, allotment, allowance,
   apportion, apportionment, appropriate, appropriation, assign,
   be affected, be in tune, be inspired, be involved, be moved,
   be partners in, big end, bigger half, bit, bite, block, board lot,
   broadcast, budget, care about, carve, carve up, catch the flame,
   catch the infection, change color, chunk, claim,
   color with emotion, commission, communicate, component, contingent,
   convey, cooperate, cross section, cut, cut up, deal, deal out,
   destiny, detachment, detail, dig, dispensation, dispense,
   disseminate, divide, divide into shares, divide up, divide with,
   dividend, division, divvy, divvy up, divvy up with, dole, dole out,
   due, dummy share, echo, empathize with, end, equal share, equity,
   even lot, experience, fate, fraction, fractional lot, full lot,
   get across, get over, give, give out, give word, go even stephen,
   go fifty-fifty, go halvers, go halves, go shares, half, halve,
   halver, hand on, helping, holding, holdings, identify with, impart,
   installment, interest, item, leave word, lot, make known, measure,
   meed, mess, mete out, modicum, moiety, odd lot, parcel, part,
   partake, participate, particular, partition, pass, pass along,
   pass on, pay out, percentage, piece, portion, preference share,
   proportion, prorate, quadrant, quantum, quarter, quota, quotient,
   quotum, rake-off, random sample, ration, react,
   relate to emotionally, remainder, render, report, respond,
   round lot, sample, sampling, section, sector, segment, send,
   send word, serving, share in, share out, share with, shift, signal,
   slice, slice the pie, slice up, small share, split,
   split the difference, split up, stake, stock, stockholding,
   stockholdings, subdivision, subgroup, subspecies, sympathize with,
   tell, transfer, transmit



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

SHARE. A portion of anything. Sometimes shares are equal, at other times
they are unequal.
     2. In companies and corporations the whole of the capital stock is
usually divided into equal proportions called shares. Shares in public
companies have sometimes been held to be real estate, but most usually they
are considered as personal property. Wordsw. Jo. Sto. Co. ch. 1 P, p. 288.
3. The proportion which descends to one of several children from his
ancestor, is called a share. The term share and share alike, signifies in
equal proportions. See Perpart.