夕闇

(1)the time of day immediately following sunset; "he loved the twilight"; "they finished before the fall of night"

(2)日没の直後

(3)the diffused light from the sky when the sun is below the horizon but its rays are refracted by the atmosphere of the earth

(4)太陽が地平線の下にあるのに光線が地上の大気に反射して空から散光していること