ejectment

Definition from Nolo’s Plain-English Law Dictionary

A lawsuit brought to remove a party who is occupying real property. This is not the same as an unlawful detainer (eviction) suit, because it is against someone who has wrongfully tried to claim title to the property, not a tenant who only has a right of possession. Example: George lives on a ranch which he claims he has inherited from his great uncle, but Betty sues for ejectment on the basis that, in fact, she was entitled to the property through her parents.

Definition provided by Nolo’s Plain-English Law Dictionary.