1. Of or like twilight; dim: "the period's crepuscular charm and a waning of the intense francophilia that used to shape the art market" (Wall Street Journal).
a. Active primarily at dawn or dusk or both. Used of animals.
b. Occurring at dawn or dusk or both: crepuscular foraging; a crepuscular stroll through the park.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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