síþ
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.
síþ
. IV. AddÁhwerfedum síþe uersa uice, An. Ox. 592. V. AddHé cóm tó his bréðer, and his síð be endebyrdnysse sǽde, Hml. Th. ii. 358, 25. VII. 1. AddǼne síþa semel, Ps. Srt. 61, 12: 88, 36. v. for-, geon-, heóf- ? (heów-) síþ; í-síþes.
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.