"small onion," 1660s, shortened from eschalot, from French échalote, from French eschalotte, from Old French eschaloigne, from Vulgar Latin *escalonia (see scallion). OED prefers shalot.
Entries linking to shallot
scallion n.
late 14c., scalun "shallot," kind of common onion, also "thing of little value," from Anglo-French escalone, Old North French escalogne, or Old French eschaloigne, all from Vulgar Latin *escalonia, from Latin (cæpa) Ascalonia "(onion) from Ascalon," the seaport in the southwestern Levant (modern Ashkelon in Israel). Cognate with shallot.