byht
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.
byht
[cf. búgan]. AddÐérdíc útt scǽtt æt ðám bihtæ, C. D. v. 74, 2. On heges byhte; of ðám byhte, iii. 419, 16. [The poetical passages should be taken separately under byht = habitation, abode. Cf. búan.]
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.