The Collaborative International Dictionary of English v.0.48:

Myth \Myth\ (m[i^]th), n. [Written also mythe.] [Gr. my^qos
   myth, fable, tale, talk, speech: cf. F. mythe.]
   1. A story of great but unknown age which originally embodied
      a belief regarding some fact or phenomenon of experience,
      and in which often the forces of nature and of the soul
      are personified; an ancient legend of a god, a hero, the
      origin of a race, etc.; a wonder story of prehistoric
      origin; a popular fable which is, or has been, received as
      historical.
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   2. A person or thing existing only in imagination, or whose
      actual existence is not verifiable.
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            As for Mrs. Primmins's bones, they had been myths
            these twenty years.                   --Ld. Lytton.
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   Myth history, history made of, or mixed with, myths.
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