on-bídan
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.
on-bídan
I. AddHé þǽr onbád sume hwíle oð flód úp eóde, Chr. 1052; P. 180, 13. II. AddÞǽr his Pompeius on ánre dúne onbád, Ors. 5, 12; S. 240, 23. IV. with clause Hé gesæt be þám swere anbídende hwæt him gelimpan scolde, Bl. H. 239, 22.
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A Combined List of Abbreviations.