Third-person singular simple present indicative form of promise.(verb)
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Use "promiseth" in a sentence
"He promiseth anything in the name of vote seeking."
"Let us not abuse the goodness of God, who calleth us mercifully to amendment, and of his endless pity promiseth us forgiveness of that which is past, if with a perfect and true heart we return unto him."
"Quoth she, “Indeed his words be many, and he still cometh and promiseth me jewels and treasures and costly stuffs; but I see nothing.”"