The Collaborative International Dictionary of English v.0.48:

Pigment \Pig"ment\, n. [L. pigmentum, fr. the root of pingere to
   paint: cf. F. pigment. See Paint, and cf. Pimento,
   Orpiment.]
   1. Any material from which a dye, a paint, or the like, may
      be prepared; particularly, the refined and purified
      coloring matter ready for mixing with an appropriate
      vehicle.
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   2. (Physiol.) Any one of the colored substances found in
      animal and vegetable tissues and fluids, as bilirubin,
      urobilin, chlorophyll, etc.
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   3. Wine flavored with species and honey. --Sir W. Scott.
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   Pigment cell (Physiol.), a small cell containing coloring
      matter, as the pigmented epithelial cells of the choroid
      and iris, or the pigmented connective tissue cells in the
      skin of fishes, reptiles, etc.
      [1913 Webster] Pigmental