'acrostical' originates from Greek, specifically the word 'akrostikhis,' where 'akro-' meant 'top' or 'end' and 'stikhos' meant 'line.'

'akrostikhis' transformed into the Latin word 'acrostichis,' and eventually became the modern English word 'acrostic' through Middle English.

Initially, it meant 'a line or verse,' but over time it evolved into its current meaning of 'a poem or word puzzle in which certain letters in each line form a word or words.'