The Collaborative International Dictionary of English v.0.48:

Alphabet \Al"pha*bet\, n. [L. alphabetum, fr. Gr. ? + ?, the
   first two Greek letters; Heb. [=a]leph and beth: cf. F.
   alphabet.]
   1. The letters of a language arranged in the customary order;
      the series of letters or signs which form the elements of
      written language.
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   2. The simplest rudiments; elements.
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            The very alphabet of our law.         --Macaulay.
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   Deaf and dumb alphabet. See Dactylology.
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