marbling
    n 1: the intermixture of fat and lean in a cut of meat

Marble \Mar"ble\, v. t. [imp. & p. p. Marbled; p. pr. & vb. n.
   Marbling.] [Cf. F. marbrer. See Marble, n.]
   To stain or vein like marble; to variegate in color; as, to
   marble the edges of a book, or the surface of paper.
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Marbling \Mar"bling\, n.
   1. The art or practice of variegating in color, in imitation
      of marble.
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   2. An intermixture of fat and lean in meat, giving it a
      marbled appearance.
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   3. pl. (Zool.) Distinct markings resembling the variegations
      of marble, as on birds and insects.
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