heriot is derived from the Anglo-Saxon word for ‘war-gear’ (in Scotland, hereyeld). This was a feudal obligation due to a lord on the death of a tenant. Originally the tenant's heir returned armour and weapons lent to him, but it developed into a claim by the lord to the best beast or chattel, and even more. It was, in effect, a kind of death duty, though its incidence varied widely. By the 14th cent. it was becoming common for the heriot to be commuted to a money payment.

J. A. Cannon

heriot (orig.) feudal service consisting of military equipment restored to the lord on the death of a tenant. OE. hereġeatwa, -we, f. here army + ġeatwa trappings.