Third person singular present of gloam; grows twilit or takes on the character of dusk.
From Old English gloam (to become dark) used as a verb. When verbed, it means the sky or environment is becoming darkened by approaching evening.
Gloam as a verb is so archaic that many dictionaries have dropped it, yet it's magical—'the sky gloams' captures something more specific than just 'darkens' because it implies that golden, liminal quality unique to twilight.
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