Tanning. Obs. [Of obscure origin; cf. LOB sb.2 5.] The infusion of bark and ooze used in tanning leather. (Cf. LOPPING vbl. sb.3)

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1773.  Encycl. Brit., III. 886/2. The bark should be rounder beat, and more given to the lop, for large hides than small ones; and consequently larger leather should lie longer in the lop.

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