Webster's Revised Unabridged Dictionary · 1913

Acronyc

Acronyc ({not transcribed}) , adjective

[Greek 'akro`nychos at nightfall; 'a`kros + ny`x night.]

(Astronomy) Rising at sunset and setting at sunrise, as a star; -- opposed to cosmical.

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

Also: Acronychal