What does acronyc or acronychal mean?
The definition of acronyc and acronychal
A*cron”yc, A*cron”ych*al, a.
Etym: [Gr. (Astron.)

Rising at sunset and setting at sunrise, as a star; — opposed to cosmical.

Note: The word is sometimes incorrectly written acronical, achronychal, acronichal, and acronical.