After seeing some words relating to a fringe or ruffle (of crepe), I had formed the opinion that ‘crepuscular’ would be related, especially as it is commonly used to describe the unusual shadows formed under clouds at sunset, where the light is blocked by the ‘fringing’ mountains nearby.
However, the Etymology lists it as meaning ‘obscured’, or ‘relating to sunset’. But it’s odd how you only see the word ‘crepuscular’ in relation to the shadows thrown by a mountain and not directly connected to the sunset itself. People never just say look at the crepuscular display tonight, unless there are those distinctive cloud shadows… I am interested in others’ opinions on this.
In the good old Campanini Carboni (Latin-Italian-Latin) I find crĕpuscŭlum (n., twilight, dusk) related to crĕpĕr (adj., dusky, dark, dubious, uncertain).
Which of course shifts the question to a reasonable “OK, but where the hell does this rarely seen crĕpĕr come from?”. Unfortunately here none of my dusty tomes seems to have an answer whatsoever, or even an educated guess.
While I cannot rule out categorically a hypothetical connection between crĕpĕr and crepe - the latter from Latin crispus (curly) - let me say that I would find it pretty far-fetched. But I’ve heard worse… 