The Collaborative International Dictionary of English v.0.48:

Tope \Tope\, v. i. [imp. & p. p. Toped (t[=o]pt); p. pr. & vb.
   n. Toping.] [F. t[^o]per to cover a stake in playing at
   dice, to accept an offer, t[^o]pe agreed!; -- perhaps
   imitative of the sound of striking hands on concluding a
   bargain. From being used in English as a drinking term,
   probably at first in accepting a toast.]
   To drink hard or frequently; to drink strong or spiritous
   liquors to excess.
   [1913 Webster]

         If you tope in form, and treat.          --Dryden.
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