Cite the scanned version of the original dicionary like this:
Bosworth, Joseph. "dóm-settend." An Anglo-Saxon Dictionary: Based on the Manuscript Collections of the Late Joseph Bosworth. Ed. Thomas Northcote Toller. Oxford: Clarendon Press, 1898. 208.
.Substitute: One who ordains judgement (v. settan, VI), a lawyer :-- Juriconsultus, jurisperitus, id est rihtscrífend sive dómsettend, Wrt. Voc. ii. 49, 13.