Third-person singular simple present indicative form of redden.(verb)
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Use "reddens" in a sentence
"Cecil reddens as I speak, but with my final words, the color drains from his face."
"The petroleum smell of napalm coughs into the child's lungs, and the tiny body reddens against the wind of his own breath."
"Since the 14th century, a substance said to be the dried blood of the martyred saint periodically liquefies and reddens, indicating good years and bad according to legend."