burna
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.
burna
AddBurna latex, Wrt. Voc. ii. 52, 16. On sumere stówe wæs getácnod swilce fordrúwod burna ... þá sceát heó inn on þone burnan, Hml. S. 23 b, 197: 740. On þone burnan þe scýt tó culan fenne, andlang þæs burnan, ... andlang heges þe scýt of þám burnan, C.D. iii. 458, 7-10. v. cweorn-, winter-burna.
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A Combined List of Abbreviations.