in Grammar, an accent serving to note, or distinguish, a syllable of an intermediate sound between acute and grave; and generally somewhat long.—The Greeks had three accents, the acute, the grave, and the circumflex; formed thus, ' , ` ~. In Latin, English, French, &c. the circumflex is made thus ^—The acute raises the voice, and the grave falls or lowers it: the circumflex is a kind of undulation, or wavering of the voice, between the two. It is seldom used among the moderns, unless to show the omission of a letter which made the syllable long and open; a thing much more frequent in the French than among us: thus they write pâte for païe; tête for tête; flûtes for flûmes, &c. They also use the circumflex in the participles; some of their authors writing connue, peu, others connû, pû, &c. Father Buffier is at a loss for the reason of the circumflex on this occasion.
The form of the Greek circumflex was anciently the same with that of ours, viz. ^; being a composition of the other two accents ^ in one.—But the copyists changing the form of the characters, and introducing the running hand, changed also the form of the circumflex accent; and instead of making a just angle, rounded it off, adding a dash, through too much haste; and thus formed an s, laid horizontally, which produced this figure ^, instead of this ^.