Webster's Revised Unabridged Dictionary · 1913

Acrostic

Acrostic ({not transcribed}) , noun

[Greek {not transcribed}; {not transcribed} extreme + {not transcribed} order, line, verse.]

1.
A composition, usually in verse, in which the first or the last letters of the lines, or certain other letters, taken in order, form a name, word, phrase, or motto.
2.
A Hebrew poem in which the lines or stanzas begin with the letters of the alphabet in regular order (as Psalm cxix.). See Abecedarian.
Collocations (1)
Double acrostic , a species of enigma<-- crossword puzzle -->, in which words are to be guessed whose initial and final letters form other words.

Acrostic ({not transcribed}) , noun

Pertaining to, or characterized by, acrostics.

Also: Acrostical