bleáþ
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.
bleáþ
AddSiþþan hié welegran wǽron, hié eác bleáðran gewurdon aurum Persicum prima Graeciae virtutis corruptio fuit , Ors. 2 5; S. 84, 22. [v. N. E. D. blethe.]
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.