pliht
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.
pliht
AddLóce hwá þás bóc áwríte, wríte hig be þǽre bysne and for Godes lufon hí gerihte, þæt heó tó leás ne beó þám wrítere tó plihte and mé tó tále, Ælfc. T. Grn. 21, 40. Tó plihte þínre ǽhta and þínes ágenes heáfdes bodað þes þín cnapa swá bealdlíce be Críste, Hml. S. 35, 32.
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A Combined List of Abbreviations.

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A Combined List of Abbreviations.