Culinary definition of fillet or filet: A boneless (not always skinless) piece of fish or meat
C@H FOOD FOR THOUGHT
Also used as a verb - fillet a fish (remove from the bone). When chosing a fillet of fish or meat, choose or create ones of uniform thickness.
This will ensure even cooking and more pleasing presentation - especially true for fish, whose natural shape is somewhat triangular and of various thicknesses.