acrostatic
adjective
ac·ro·stat·ic ˌa-krə-ˈsta-tik 
of Indo-European noun inflection
: retaining accent on the root throughout the paradigm (see paradigm sense 2) with zero-grade ablaut of the stem and ending
Word History
Etymology
borrowed from German akrostatisch, from akro- acro- + -statisch -static
First Known Use
1978, in the meaning defined above