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. {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. Abecedary \A`be*ce"da*ry\, n. A primer; the first principle or rudiment of anything. [R.] --Fuller.