hrúm
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.
hrúm
AddHrúm cacobatus, Wrt. Voc. ii. 17, 37. Hrúme fuligine, 34, 42. Nim ceteles hrúm, Lch. ii. 148, 10.
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.