The Collaborative International Dictionary of English v.0.48:

Portraiture \Por"trai*ture\, v. t.
   To represent by a portrait, or as by a portrait; to portray.
   [R.] --Shaftesbury.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Portraiture \Por"trai*ture\ (?; 135), n. [F. portraiture.]
   1. A portrait; a likeness; a painted resemblance; hence, that
      which is copied from some example or model.
      [1913 Webster]

            For, by the image of my cause, I see
            The portraiture of his.               --Shak.
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            Divinity maketh the love of ourselves the pattern;
            the love of our neighbors but the portraiture.
                                                  --Bacon.
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   2. Pictures, collectively; painting. [Obs.] --Chaucer.
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   3. The art or practice of making portraits. --Walpole.
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WordNet (r) 3.0 (2006):

portraiture
    n 1: a word picture of a person's appearance and character [syn:
         portrayal, portraiture, portrait]
    2: the activity of making portraits