scrybb
This might be just a supplemental entry adding to an entry in the Main Volume.
In the OE text, the length is:indicated by acute accentsindicated by macronsnot indicated.
scrybb
AddAndlang scrybbe(?), C. D. B. iii. 603, 28. [To one weie þet geþ to Winchestre þat is ihoten shrubbeshedde bitwiene þe shrubbes, i. 58, 10. See Philol. Trans. 1895, 8, p. 536.]
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.