birce
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.
birce
AddBirciae, birce populus, Txts. 88, 792. Birce, Wrt. Voc. i. 285, 22. Byrce, ii. 68, 25. Birce beta, i. 285, 38: ii. 11, 57. Byrce betulus, 12, 65. Beeástan ðá bircan, C. D. iii. 213, 3. In ðá twislihtran biricean, 391, 21. v. beorc.
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.