dop-fugel
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.
dop-fugel
AddDopfugel mergus, Hpt. 33, 240, 23. Mergulum, niger avis, mergit sub aquam pisces quaerere, i. e. dobfugel, Shrn. 29, 4. Ðæs gífran dopfugeles voracis mer[g]ule, Wrt. Voc. ii. 76, 7: 56, 61. [O. L. Ger. dop-fugul.]
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.