According to Merriam-Webster, crepuscular means:

1. of, relating to, or resembling twilight, eg: crepuscular light
2. occurring or active during twilight, eg: crepuscular insects

I recently read the word crepuscular in a lovely passage in Joseph Conrad’s Lord Jim. Here is the passage:

The whisper of his conviction seemed to open before me a vast and uncertain expanse, as of a crepuscular horizon on a plain at dawn—or was it perchance, at the coming of night? One had not the courage to decide; but it was a charming and deceptive light, throwing the impalpable poesy of its dimness over pitfalls—over graves. His life had begun in sacrifice, in enthusiasm for generous ideas; he had travelled very far, on various ways, on strange paths, and whatever he followed it had been without faltering, and therefore without shame and without regret. In so far he was right. That was the way, no doubt. Yet for all that the great plain on which men wander amongst graves and pitfalls remained very desolate under the impalpable poesy of its crepuscular light, overshadowed in the centre, circled with a bright edge as if surrounded by an abyss full of flames.

My own sentence(s) using the word crepuscular:

We tarry by the riverside
Under the wide crepusculum.
It will soon be dark,
too dark to see.
We’ll stumble like blind men
toward the ferry.