crepuscular

/kɹɪˈpʌs.kjʊ.lə/

Etymology

Learned borrowing from Latin crepusculum + -ar.

Why this word is great

CREPUSCULAR — [Adjective] Of, relating to, or resembling twilight; or, in zoology, active during dawn and dusk. From Latin crepusculum ("twilight") + -ar (adjective-forming suffix), with crepusculum possibly related to creper ("obscure"). Unlike "nocturnal" (which claims the full night) or "dusky" (which merely dims), crepuscular thrives in the in-between—the fox slipping through the hedgerow at daybreak, the moth trembling toward the last violet streak of dusk, or the way a room holds its breath in that suspended moment when the lamps are lit but the sun hasn’t quite surrendered. It is the quiet triumph of the transitional, the beauty of what refuses to belong.

adj

Of or resembling twilight; dim.
Active at or around dusk, dawn or twilight.“That's why cats are crepuscular — most active at dawn and dusk — because mice and rats forage for food during these hours when fewer of their natural enemies are around.”