fæst-mód
This might be just a supplemental entry adding to an entry in the Main Volume.
Related §§ in Wright's OE Grammar:
In the OE text, the length is:indicated by acute accentsindicated by macronsnot indicated.
fæst-mód
of constant mind, steadfast. AddHé tómiddes þám líge tó Gode ánmódlíce clypode, and on þǽre frecednysse fæstmód þurhwunode, Hml. S. 31, 872. [The Latin in Ors. 6, 33 is: Tantam constantiam pro retinenda fide quondam habuisset. ' ]
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.