A more thorough explanation:

Definition: A Saxon freeman who either possessed no landed property or held land of a thane by paying rent or providing services. After the Norman Conquest, ceorls were reduced to the status of unfree villeins. Under Norman rule, the variant form of the word, churl, became associated with a base peasant, and soon acquired the connotation of a surly, coarse person (hence the modern meaning).

Example: In Saxon times, a ceorl was a freeman who did not own any land or held land by paying rent or providing services to a thane. However, after the Norman Conquest, they were reduced to the status of unfree villeins.

Explanation: The example illustrates how the status of a ceorl changed after the Norman Conquest. Before the conquest, they were considered freemen, but after the conquest, they lost their freedom and became unfree villeins. This shows how the conquest had a significant impact on the social structure of England.