un-gewiss
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.
un-gewiss
ad/. I. AddHé him þá gewát swíðe gewisfullíce (-wiss- v.l.) swilce hé ungewis wǽre recessit scienter nescius, Gr. D. 95 30. Ungewiss for costnunge per tentalionem imperita, 265, 9. Hí beóð deáde and ungewisse þæs écan lífes, 264, 10.
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.