sméþness
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.
sméþness
II. AddÞǽr náhwǽr næs nǽnigu sméðnes man mihte áht tó þan lytelne wyrtún þám bróþrum tó nytte gewyrcan ad quemlibet parvum hortum fratribus excolendum nulla patebat planities, Gr. D. 49, 4. [v. N. E. D. smeethness.] v. un-sméþness.
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.