lettan
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.
lettan
Add:1. to hinder a person, thing, action, &c. Ne leteð non tricaverit (si lethi somnus palpebrarum convolatus nan tricaverit, Ald. 80, 20), Wrt. Voc. ii. 88, 36. Let, An. Ox. 8b, 6. 2. the action from which one is hindered given in genitive Wé þé þæs nú nellað lettan þæs þú ǽr geþóht hæfdest propositi tui ortnonomias dirumpere nolumus, Guth. Gr. 123, 20.
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A Combined List of Abbreviations.