What is a person of high rank who owned land but owed loyalty to his king called?

A person of high rank who owned land but owed loyalty to a king is called a "noble" or "lord." In the context of feudalism, these individuals were part of the aristocracy and held significant power and influence within their territories, often managing the land and its inhabitants in exchange for military support to the king. Their loyalty was crucial for maintaining the social and political structure of the time.