The Collaborative International Dictionary of English v.0.48:

Nepenthe \Ne*pen"the\, n. [Fr. Gr. ? removing all sorrow; hence,
   an epithet of an Egyptian drug which lulled sorrow for the
   day; ? not + ? sorrow, grief.]
   A drug used by the ancients to give relief from pain and
   sorrow; -- by some supposed to have been opium or hasheesh.
   Hence, anything soothing and comforting.
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         Lulled with the sweet nepenthe of a court. --Pope.
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         Quaff, O quaff this kind nepenthe.       --Poe.
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