in Anglo-American property law, holding of property under some claim of right with the knowledge and against the will of one who has a superior ownership interest in the property. Its legal significance is traced back to the English common-law concept known as seisin, a possession of land by one who owns the property at least for the period of his life, having a complete right to possession of the property as against all others. The possession by any other under some claim of right to the land was known as disseisin. One who was disseised of his property could take the matter to the king's court through a legal action known as the assize of novel disseisin. If the land held by a disseisor was claimed by an heir of the original owner in seisin, the heir could bring a similar legal action known as the assize of mort d'ancestor. After the 17th century more expeditious legal actions were developed.

In the United States, disseisin developed as the concept of adverse possession. Statutes of limitation in most of the U.S. states set time limits within which an owner can bring an action for possession, after which time an adverse possessor acquires a legal title to the land.