The Collaborative International Dictionary of English v.0.48:

Fat \Fat\, a. [Compar. Fatter; superl. Fattest.] [AS.
   f[=ae]tt; akin to D. vet, G. fett, feist, Icel. feitr, Sw.
   fet, Dan. fed, and perh. to Gr. pi^dax spring, fountain,
   pidy`ein to gush forth, pi`wn fat, Skr. pi to swell.]
   1. Abounding with fat; as:
      (a) Fleshy; characterized by fatness; plump; corpulent;
          not lean; as, a fat man; a fat ox.
      (b) Oily; greasy; unctuous; rich; -- said of food.
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   2. Exhibiting the qualities of a fat animal; coarse; heavy;
      gross; dull; stupid.
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            Making our western wits fat and mean. --Emerson.
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            Make the heart of this people fat.    --Is. vi. 10.
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   3. Fertile; productive; as, a fat soil; a fat pasture.
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   4. Rich; producing a large income; desirable; as, a fat
      benefice; a fat office; a fat job.
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            Now parson of Troston, a fat living in Suffolk.
                                                  --Carlyle.
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   5. Abounding in riches; affluent; fortunate. [Obs.]
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            Persons grown fat and wealthy by long impostures.
                                                  --Swift.
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   6. (Typog.) Of a character which enables the compositor to
      make large wages; -- said of matter containing blank,
      cuts, or many leads, etc.; as, a fat take; a fat page.
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   Fat lute, a mixture of pipe clay and oil for filling
      joints.
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