- nepenthe (n.)
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- 1570s, nepenthes, from Greek nepenthes, from ne- "no, not" (see un-) + penthos "pain, grief," from PIE *kwent(h)- "to suffer" (see pathos). A drug of Egypt mentioned in the "Odyssey" as capable of banishing grief or trouble from the mind. The -s is a proper part of the word, but likely was mistaken in English as a plural affix and dropped.