an enlargement of the digestive tract of birds, immediately following the crop1 (pouchlike part of the gullet), that has thick muscular walls and usu contains small stones or grit for breaking up and grinding food
a thickened or enlarged part of the digestive tract in some invertebrate animals, e.g. an insect or earthworm, that is similar in function to the gizzard of a bird
[alteration of Middle English giser from early French guisier, from Latin gigeria giblets]