Definition - What does Ejectment mean?
Ejectment is legal grounds for a lawsuit that can be brought by a property owner to remove a third party from their premises. The difference between ejectment and eviction is that in ejectment, the person did not have the legal right to be there, i.e. they were squatting on the property without a valid lease. An ejectment procedure is otherwise the same as an eviction but can be effected immediately in most states.
Justipedia explains Ejectment
There are times when the squatter would claim that they in fact had the right to maintain a presence on the property and potentially gain adverse possession over the property. The judge would then consider whether they had a legal claim, and if not, the ejectment would be issued.