bises
This might be just a supplemental entry substituting part of an entry in the Main Volume.
In the OE text, the length is:indicated by acute accentsindicated by macronsnot indicated.
bises
Substitute: The intercalary day in leap year, bissext (v. N. E. D.) Bútan þænne bises geboden weorðe feórðan geáre except when bissext is ordered every fourth year, Men. 32. v. bissextus.
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.