noun

1. any of a family (Pectinidae) of bivalves with two deeply grooved, convex shells and an earlike wing on each side of the hinge, that swims by rapidly snapping its shells together to expel water in a jetlike manner
2. the edible large adductor muscle of such a mollusk
3. the single shell of such a mollusk; specif.,
   1. one worn formerly as a badge by pilgrims returning from the Holy Land
   2. one, or a dish shaped like one, in which fish or other food is baked and served
4. any of a series of curves, circle segments, projections, etc. forming an ornamental edge on cloth, lace, etc.

Etymology: ME scalop < OFr escalope < escale: see scale

transitive verb

1. to cut the edge or border of in scallops
2. to bake until brown, as in a casserole, usually with a creamy sauce and a topping of bread crumbs

intransitive verb