Superlative form of swift: most swift. (adjective)
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Use "swiftest" in a sentence
"Now the whole spindle has the same motion; but, as the whole revolves in one direction, the seven inner circles move slowly in the other, and of these the swiftest is the eighth; next in swiftness are the seventh, sixth, and fifth, which move together; third in swiftness appeared to move according to the law of this reversed motion, the fourth; the third appeared fourth, and the second fifth."
"She was called the swiftest cotton picker on the place, but since the birth of her child it had been somewhat of a burden for her to perform her daily task."
"The error is of the nature of a half-truth, the most dangerous of errors; for it is true that, as compared with land forces, the great characteristic of navies is mobility; but it is not true that, between different classes of naval vessels, the swiftest are the most efficient for control of the sea."