Circumflex: Curved like a bow. In anatomy, circumflex describes a structure that bends around like a bow. For example, the circumflex branch of the left coronary artery.
In linguistics, a circumflex is a caret-shaped mark (^) used over a vowel to indicate the pronunciation, length or the omission of a letter formerly pronounced. In French, it is called "un petit chapeau" (a little hat).
From the Latin circumflexus, bent around, circumflex, past participle of circumflectere, to bend around : circum- + flectere, to bend.