eorþ-beofung
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.
eorþ-beofung
AddWæs in Achie eorþbeofung, and twá byrig on eorþan besuncon terrae motu Achaia concussa est, et duae civitates abruptis locorum hiatibus devoratae sunt, Ors. 3, 2 ; S. 100, 18: 3, 9 ; S. 132, 13.
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.