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]