rapier

A rapier is a straight, two-edged sword with a narrow pointed blade, designed especially for thrusting. According to Encyclopædia Britannica, "the long rapier was beautifully balanced, excellent in attack, and superb for keeping an opponent at a distance." The word itself, which we borrowed in the 16th century, is from Middle French rapiere. The first time that rapier was used as an adjective in its figurative "cutting" sense, it described a smile: "Who can bear a rapier smile? A kiss that dooms the soul to death?" ("The Lover's Lament" by Sumner Lincoln Fairfield, 1824). The adjective these days most commonly describes wit-an association that dates to the 1850s.