Grand chop

from The Collaborative International Dictionary of English v.0.48

Chop \Chop\, n. [Chin. & Hind. ch[=a]p stamp, brand.]
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   1. Quality; brand; as, silk of the first chop.
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   2. A permit or clearance.
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   {Chop dollar}, a silver dollar stamped to attest its purity.
      

   {chop of tea}, a number of boxes of the same make and quality
      of leaf.

   {Chowchow chop}. See under {Chowchow}.

   {Grand chop}, a ship's port clearance. --S. W. Williams.
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