a traditional pudding made of the heart, liver, etc., of a sheep or calf, minced with suet and oatmeal, seasoned, and boiled in the stomach of the animal.
Origin: 1375–1425; late ME hageys < AF *hageis, equiv. to hag- (root of haguer to chop, hash < MD hacken to hack1) + -eis n. suffix used in cookery terms
c.1420, now chiefly Scot., but common in M.E., perhaps from O.Fr. agace "magpie," on analogy of the odds and ends the bird collects. The other theory traces it to O.E. haggen "to chop" (see hack (1)).
[hag-is] 
