You searched for: “acronych
acronych (adjective) (not comparable)
Descriptive of an occurrence in the evening; vespertine: It can be said that a star is acronych when it appears at dusk.

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 Oxford English Dictionary)

This entry is located in the following units: acro-, acr- (page 6) -al; -ial, -eal (page 6)