1) Poem 2) Verse form 
An abecedarius is an acrostic in which the first letter of every word, strophe or verse follows the order of the alphabet. Abecedarius is also a generic term for an alphabet book, which dates back to Biblical writings such as the Psalms, which used successive letters of the Hebrew alphabet as the first letter of each stanza. ...
a type of acrostic in which the first letter of each line of a poem or the first letter of the first word of each stanza taken in order forms the ... [1 related articles]
[n] - a poem having lines beginning with letters of the alphabet in regular order
noun a poem having lines beginning with letters of the alphabet in regular order