[n] verse in which certain letters such as the first in each line form a word or message
[n] a puzzle where you fill a square grid with words reading the same down as across
A poem, 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.
Here is an example in English, an Edgar Allan Poe poem titled simply An Acrostic:
Elizabeth it is in vain you say
"Love not" — thou sayest it in so sweet a way: In vain those words from thee or L.E.L. Zantippe's talents had enforced so well: Ah! if that language from thy heart arise, Breath it less gently forth — and veil thine eyes. Endymion, recollect, when Luna tried To cure his love — was cured of all beside — His follie — pride — and passion — for he died.
literary composition, literary work, problem