Dawn; sunrise; the moment at which the sun can first be seen on the horizon.(noun)
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Use "first light" in a sentence
"A Roman writer describes the situation concisely: and having hastily found a suitable guide from among the Picentine prisoners, he Spartacus made his way hidden in the Eburian Hills to Nares Lucanae and from there at first light he reached Forum Annii."
"It was first light when Spartacuss men reached the little town of Forum Annii."
"By the time the sun cast its first light over the plains, Alfred was out with the two drays and a wagon, searching for Sage."