on-drǽdendlic
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-drǽdendlic
Add:I. tremendous Ic eów bidde ðurh þæne ondrǽdendlican dómes dæg, Hml. A. 145, 41. II. fearful, in terror Wearð eorþbeofung . . . Hié þeah swá ondrǽdendlice (andrǽdende, v. l.) gebidon terra tremuit. Diu adtoniti utrimque populi haesitavere, Ors. 4, 2 ; S. 160, 30.
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A Combined List of Abbreviations.