The Collaborative International Dictionary of English v.0.48:

Owl \Owl\, v. i. [imp. & p. p. Owled; p. pr. & vb. n.
   Owling.]
   1. To pry about; to prowl. [Prov. Eng.]
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   2. To carry wool or sheep out of England. [Obs.]
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   Note: This was formerly illegal, and was done chiefly by
         night.
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   3. Hence, to carry on any contraband trade. [Eng.]
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