The term occupy is mainly used in the Occupy Movement for occupation of public places. Maybe the term was chosen from the philosophy of peaceful anarchists who think that the one who makes use of real estate shall have the owner rights for that ground. The political implication of the term is that people feel uncomfortable with having to obey so many laws which restrict public assemblies. Occupiers oppose to such rules and say that public places must be owned by all and usable for any assembly w/o request to authorities.