ofer-tredan
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.
ofer-tredan
AddFlíhð ǽlc hors áfǽred ðurh ðá ylpas, and gif him hwá wiðstent hé byð sóna ofertreden (oftreden, v. l. ], Hex. 16, 14. [v. N. E. D. over-tread.]
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.