rihtan
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.
rihtan
I. add: to put right, put into a proper condition Á hé mæig findan hwæt hé mæig on byrig bétan . . . oððe hús gódian, rihtan and weoxian, Angl. ix. 262, 18. IV. AddHé riht (reht, v. l. ) and rǽt callum gesceaftum, Bt. 35, 3; F. 158, 25. Simplicius wæs þridda þe æfter Benedicte rihte his gesomnunge Simplicius congregationem illius post eum tertius rexit, Gr. D. 96, 12.
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.