The Collaborative International Dictionary of English v.0.48:

Prog \Prog\, n.
   1. Victuals got by begging, or vagrancy; victuals of any
      kind; food; supplies. [Slang] --Swift.
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            So long as he picked from the filth his prog. --R.
                                                  Browning.
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   2. A vagrant beggar; a tramp. [Slang]
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   3. A goal; progue. [Scot.]
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The Collaborative International Dictionary of English v.0.48:

Prog \Prog\, v. i. [imp. & p. p. Progged. p. pr. & vb. n.
   Progging.] [Cf. D. prachen, G. prachern, Dan. prakke, Sw.
   pracka, to beg, L. procare, procari, to ask, demand, and E.
   prowl.]
   1. To wander about and beg; to seek food or other supplies by
      low arts; to seek for advantage by mean shift or tricks.
      [Low]
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            A perfect artist in progging for money. --Fuller.
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            I have been endeavoring to prog for you. --Burke.
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   2. To steal; to rob; to filch. [Low] --Johnson.
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   3. To prick; to goad; to progue. [Scot.]
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