thirdings

Wiktionary

1. n. UK, law One third of the corn or grain growing on the ground at the tenant's death, paid to the lord as a heriot.

GNU Webster's 1913

1. n. (Eng. Law) The third part of the corn or grain growing on the ground at the tenant's death, due to the lord for a heriot, as within the manor of Turfat in Herefordshire.