n.1 the second part of a bird's stomach, for grinding food usu. with grit.
2 a muscular stomach of some fish, insects, molluscs, and other invertebrates.
Phrases and idioms:
stick in one's gizzard colloq. be distasteful.
Etymology: ME giser f. OF giser, gesier etc., ult. f. L gigeria cooked entrails of fowl