Definition of "civey"

In the kitchens the famous cooks were preparing menus which included, for one course alone: ballock broth, caudle ferry, lampreys en gelatine, oysters in civey, eels in sorré, baked trout, brawn in mustard, numbles of a hart, pigs farsed [...].

1940, TH White, The Ill-Made Knight

Were there served, as in former times, a wine of Grenache and roasts, veal pasties, pimpernel pasties, black pudding and sausages, hares in civey and cutlets, pea soup, salt meat and great joints, a soringue of eels and other fish...

1954, Austryn Wainhouse, Hedyphagetica‎, page 132

White leeks, beef pasties, ducks and chines, hares and coneys in civey, a geneste (p. 174) of larks, great joints.

2006, Eileen Power, editor, The Goodman of Paris (Le Ménagier de Paris): A Treatise on Moral and Domestic Economy by a Citizen of Paris, C.1393‎, page 151