byrst
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.
byrst
loss. Add:I. injury Se byrst wyrð gemǽne, Wlfst. 159, 3. Fela byrsta (bersta), 157, 1: 128, 4. II. failure, v. teám-byrst; cf. berstan, I. 2. III. a cash; cf. berstan, II. Byrstum creporibus, Wrt. Voc. ii. 136, 83. [v. N. E. D. burst. O. H. Ger. brust.]
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.