late 15c., "strap passing under the jaw of a horse," from O.Fr. courbe
"curve, curb," from L. curvus
, from curvare
"to bend" (see curve
). Meaning "enclosed framework" is from 1510s, probably originally with a notion of "curved;" extended to margins of garden beds 1731; to "margin of stone between a sidewalk and road" 1836 (sometimes spelled kerb
). The verb (1520s) is from the notion of putting a curb on a horse; fig. sense first attested 1580s.