The Collaborative International Dictionary of English v.0.48:

Portrait \Por"trait\, n. [F., originally p. p. of portraire to
   portray. See Portray.]
   1. The likeness of a person, painted, drawn, or engraved;
      commonly, a representation of the human face painted from
      real life.
      [1913 Webster]

            In portraits, the grace, and, we may add, the
            likeness, consists more in the general air than in
            the exact similitude of every feature. --Sir J.
                                                  Reynolds.
      [1913 Webster]

   Note: The meaning of the word is sometimes extended so as to
         include a photographic likeness.
         [1913 Webster]

   2. Hence, any graphic or vivid delineation or description of
      a person; as, a portrait in words.
      [1913 Webster]

   Portrait bust, or Portrait statue, a bust or statue
      representing the actual features or person of an
      individual; -- in distinction from an ideal bust or
      statue.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Portrait \Por"trait\, v. t.
   To portray; to draw. [Obs.] --Spenser.
   [1913 Webster]

WordNet (r) 3.0 (2006):

portrait
    n 1: a word picture of a person's appearance and character [syn:
         portrayal, portraiture, portrait]
    2: any likeness of a person, in any medium; "the photographer
       made excellent portraits" [syn: portrait, portrayal]

Moby Thesaurus II by Grady Ward, 1.0:

117 Moby Thesaurus words for "portrait":
   Telephoto, Wirephoto, account, aerial photograph,
   black-and-white photograph, cameo, candid photograph, catalog,
   cataloging, certified copy, character, character sketch,
   characterization, cheesecake, chronophotograph, color photograph,
   color print, companion, copy, counterfeit, dead ringer,
   delineation, depiction, description, details, diapositive, dossier,
   double, duplicate, ectype, effigy, evocation, exact likeness,
   fair copy, faithful copy, fake, fellow, file, forgery,
   graphic account, head, heliochrome, heliograph, icon, idol, image,
   imagery, imitation, impression, itemization, likeness, limning,
   living image, living picture, match, mate, miniature, mirroring,
   model, montage, mug, mug shot, particularization, pasticcio,
   pastiche, phony, photo, photobiography, photochronograph,
   photograph, photomap, photomicrograph, photomontage, photomural,
   picture, picturization, pinup, portraiture, portrayal, profile,
   record, reflection, rendering, rendition, representation,
   resemblance, ringer, rubbing, semblance, shadow, shot, silhouette,
   similitude, simulacrum, sketch, slide, snap, snapshot,
   specification, spit, spit and image, spitting image, still,
   still photograph, story, study, telephotograph, thumbnail sketch,
   trace, tracing, transparency, twin, very image, very picture,
   vignette, vivid description, word painting