The Collaborative International Dictionary of English v.0.48:

Symbolize \Sym"bol*ize\, v. i. [imp. & p. p. Symbolized; p.
   pr. & vb. n. Symbolizing.] [Cf. F. symboliser.]
   1. To have a resemblance of qualities or properties; to
      correspond; to harmonize.
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            The pleasing of color symbolizeth with the pleasing
            of any single tone to the ear; but the pleasing of
            order doth symbolize with harmony.    --Bacon.
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            They both symbolize in this, that they love to look
            upon themselves through multiplying glasses.
                                                  --Howell.
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   2. To hold the same faith; to agree. [R.]
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            The believers in pretended miracles have always
            previously symbolized with the performers of them.
                                                  --G. S. Faber.
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   3. To use symbols; to represent ideas symbolically.
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The Collaborative International Dictionary of English v.0.48:

Symbolize \Sym"bol*ize\, v. t.
   1. To make to agree in properties or qualities.
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   2. To make representative of something; to regard or treat as
      symbolic. "Some symbolize the same from the mystery of its
      colors." --Sir T. Browne.
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   3. To represent by a symbol or symbols.
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WordNet (r) 3.0 (2006):

symbolize
    v 1: express indirectly by an image, form, or model; be a
         symbol; "What does the Statue of Liberty symbolize?" [syn:
         typify, symbolize, symbolise, stand for,
         represent]
    2: represent or identify by using a symbol; use symbols; "The
       poet symbolizes love in this poem"; "These painters believed
       that artists should symbolize" [syn: symbolize,
       symbolise]

Moby Thesaurus II by Grady Ward, 1.0:

72 Moby Thesaurus words for "symbolize":
   advert to, allude to, argue, be construed as, be taken as, bespeak,
   betoken, body forth, breathe, catch a likeness, character,
   characterize, chart, connote, delineate, denominate, denote,
   depict, designate, diagram, draw, emblematize, embody, epitomize,
   exemplify, express, figure, finger, hit off, illustrate, imply,
   import, indicate, limn, map, mean, metaphorize, mirror, name,
   notate, paint, personalize, personify, pick out, picture,
   picturize, point at, point out, point to, portray, print, refer to,
   register, render, represent, rub, schematize, select, signify,
   similize, specify, spell, stand for, stigmatize, suggest, symbol,
   take a rubbing, trace, trace out, trace over, typify, write