GNU Collaborative International Dictionary of English

Found one definition

1.       
   Sup (sŭp), v. t. [imp. & p. p. Supped (?); p. pr. & vb. n. Supping.] [OE. soupen to drink, AS. sūpan; akin to D. zuipen, G. saufen, OHG. sūfan, Icel. sūpa, Sw. supa, Dan. söbe.  Cf. Sip, Sop, Soup, Supper.] To take into the mouth with the lips, as a liquid; to take or drink by a little at a time; to sip.
   
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   There I'll sup
   
   Balm and nectar in my cup. Crashaw.
   
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