Cite the scanned version of the original dicionary like this:
Bosworth, Joseph. "fisc-noþ." An Anglo-Saxon Dictionary: Based on the Manuscript Collections of the Late Joseph Bosworth. Ed. Thomas Northcote Toller. Oxford: Clarendon Press, 1898. 289.
.Substitute :fiscnoþ (-naþ), fixnoþ, es; m.I.fishing, the action or practice of taking fish, (1) by persons :-- Heora fixnoðe gelamp micel earfoðnys . . . Wé rǽdað . . . þæt Drihten héte tuwa áwurpan net on fixnoðe, ǽne ǽr his ðrowunge, and óðre síðe æfter his ǽriste . . . Se ǽrra fixnoð getácnode þás andwerdan gelaðunge . . ., and se æftra fixnoð getácnode þá tówerdan gelaðunge gecorenra manna tó ðám écan lífe. On ðám ǽrran fixnoðe wurdon swá fela gelæhte þæt þæt net tóbærst . . .
.Add:IV.the privilege or right of catching fish in certain waters :-- Ic geann þam munecum tó fódan ealne þone fixnoð þe Ulfkytel áhte æt Wyllan (piscationem quam Ulfkytel habuit in Wylla), Cht. Th. 307, 35.