Cite the scanned version of the original dicionary like this:
Toller, T. Northcote, and Joseph Bosworth. "fǽtt." An Anglo-Saxon Dictionary: Based on the Manuscript Collections of the Late Joseph Bosworth : Supplement. Oxford: Clarendon Press, 1921. 204.
;part. Covered with gold, gilt, golden, ornamented; bracteātus :-- Sincgestreónum fættan goldes with precious treasures of rich gold, Beo. Th. 2190; B. 1093: 4484; B. 2246. Fættan golde with rich gold, 4210; B. 2102. Hwanon ferigeaþ gé fætte scyldas whence bear ye your ornamented shields? 672; B. 333. v. fæted.