Word Study
au gratin
CIDE DICTIONARY
au gratin, [F.].
With a crust made by browning in the oven, especially by sprinkling with bread crumbs or grated cheese and browning in a broiler; as, spaghetti may be served au gratin. [Webster 1913 Suppl.]
OXFORD DICTIONARY
au gratin, adj. Cookery cooked with a crisp brown crust usu. of breadcrumbs or melted cheese.
Etymology
F f. gratter, = by grating, f. GRATE(1)
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