Early 17th century; earliest use found in John Lightfoot (1602–1675), Hebraist and biblical scholar. Either from acrostical + -ly, or from acrostic + -ally.
Definition of acrostically in US English:
acrostically
adverbəˈkrɒstɪkli
In the manner of an acrostic.
Origin
Early 17th century; earliest use found in John Lightfoot (1602–1675), Hebraist and biblical scholar. Either from acrostical + -ly, or from acrostic + -ally.