seóþan
This might be just a supplemental entry adding to an entry in the Main Volume.
Related §§ in Wright's OE Grammar:
In the OE text, the length is:indicated by acute accentsindicated by macronsnot indicated.
seóþan
I. AddHé seáþ coquebat, Germ. 395, 391. Se déma hét hí lǽdan sóna and seóðan on wætere (belúcan on byrnendum baðe, Shrn. 150, 1), Hml. S. 34, 343. II. 1. AddSwá swá gold on ofne hé hié sýð and costað in fornace probatur aurum; tu, ut sorde careas, tribulationis camino purgaris, Verc. Först. 141, 21. v. ge-seóþan; níw-soden.
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.