hærn
This might be just a supplemental entry substituting part of 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.
hærn
Substitute for passages Hraen, raen fiustra, undae, Txts. 60, 400. Flód oððe hærn flustra, Wrt. Voc. ii. 33, 32. Hærn eft onwand árýða geblond, An. 531.
This is a supplementary entry with editorial changes to an entry in the main volume of the dictionary. Look under the 'Possibly connected entries' below, or for the same headword in the list to the left.

A Combined List of Abbreviations.

Abbreviation not recognized. See:

A Combined List of Abbreviations.