Feudal system and Social organisation

Feudal system noun - The social system that developed in Europe in the 8th century; vassals were protected by lords who they had to serve in war.

Social organisation and feudal system are semantically related. In some cases you can use "Social organisation" instead a noun phrase "Feudal system".

Social organisation noun - The people in a society considered as a system organized by a characteristic pattern of relationships.

Feudal system and social organisation are semantically related. Sometimes you can replace phrase "Feudal system" with "Social organisation", this phrases are similar.