[fi-ley, fee-ley] 
| a powder made from the ground leaves of the sassafras tree, used as a thickener and to impart a pungent taste to soups, gumbos, and other dishes. |
| fi·lé (fē'lā, fĭ-lā') n. Powdered sassafras leaves used to thicken and season soups, stews, and gumbos. [Louisiana French, from French, past participle of filer, to spin thread (from its effect when added to hot liquids), from Old French; see file1.] |