A more thorough explanation:

Definition: Heriot is a tribute of goods and chattels that was payable to the lord of the fee on the tenant's death. It was a customary tribute that originated from an earlier feudal service consisting of military equipment returned to the lord on the tenant's death. Over time, it came to refer only to the chattel payment due at the tenant's death.

Example: In medieval times, when a tenant in villeinage died, the lord of the fee would take the best beast or a similar due from the goods of the dead freeholder as a heriot. This was a customary due that was taken from the tenant's estate and paid to the lord of the fee.

Explanation: The example illustrates how heriot was a customary tribute that was payable to the lord of the fee on the tenant's death. It was a tribute that was taken from the tenant's estate and paid to the lord of the fee. The tribute could be in the form of the best beast or a similar due from the goods of the dead freeholder.

Heriot custom: Heriot custom is a heriot due by custom. This term is used primarily to distinguish a heriot service from an ordinary heriot.

Heriot service: Heriot service is a tribute arising from special reservation in a grant or lease of lands, and thus amounting to little more than rent.