• (a.) Acronycal.
Ac'ro·nyc'tous adjective [ Greek 
acronych, acronychal, acronyctous Happening in the evening or at night-fall, vespertine, as the acronychal rising or setting of a star. Sometimes this term is used as if `rising in the evening or at sunset and setting at sunrise”; but this is not correct. When the rising is acronychal, the setting is cosmical, and vice versa. (According to the Ox...