The Collaborative International Dictionary of English v.0.48:

Abecedarian \A`be*ce*da"ri*an\, Abecedary \A`be*ce"da*ry\, a.
   Pertaining to, or formed by, the letters of the alphabet;
   alphabetic; hence, rudimentary.
   [1913 Webster]

   Abecedarian psalms, hymns, etc., compositions in which
      (like the 119th psalm in Hebrew) distinct portions or
      verses commence with successive letters of the alphabet.
      --Hook.
      [1913 Webster]