The definition of a nemesis is an enemy who can't be beaten.(noun)
An example of a nemesis is Lex Luther to Superman.
See nemesis in Webster's New World College Dictionary
noun pl. nemeses
Origin: L < Gr nemein, to distribute, deal out: see -nomy
See nemesis in American Heritage Dictionary 4
noun pl. nem·e·ses (-sēzˌ)
Origin: Greek, retribution, the goddess Nemesis
Origin: , from nemein, to allot; see nem- in Indo-European roots.
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