{ } a. [ Cf. F. crépusculaire. ] 1. Pertaining to twilight; glimmering; hence, imperfectly clear or luminous. [ 1913 Webster ]

This semihistorical and crepuscular period. Sir G. C. Lewis. [ 1913 Webster ]

2. (Zool.) Flying in the twilight or evening, or before sunrise; -- said certain birds and insects. [ 1913 Webster ]

Others feed only in the twilight, as bats and owls, and are called crepuscular. Whewell. [ 1913 Webster ]