Atenement (from the Latintenereto hold), in law, is anything that is held, rather than owned. This usage is a holdover fromfeudalism, which still forms the basis of property law in manycommon law jurisdictions, in which themonarch alone owned theallodial title to all the land within hiskingdom.
Under feudalism, land itself was never privately "owned" but rather was "held" by atenant (from Latinteneo "to hold") as afee, being merely a legal right over land known in modern law as anestate in land. This was held from a superioroverlord, (amesne lord), or fromthe crown itself in which case the holder was termed atenant-in-chief, upon some manner of service under one of a variety offeudal land tenures. The thing held is called a tenement, the holder is called atenant, the manner of his holding is called atenure, and the superior is called thelandlord, or lord of the fee. These forms are still preserved in law, even though feudalism itself is extinct, because all real estate law has developed from them over centuries.
Feudal land tenure existed in many varieties. The sole surviving form in the United States is that species offreehold known asfreesocage. Here the service to be performed is known and fixed, and not of a base or servile nature; the "lord of the fee" is the State itself, and the service due to this "lord" is payment of the taxes upon the real estate. The major consequences, in the modern world, of this feudal approach, as distinguished from ownership, are, first, theforfeiture of the tenement upon failure to perform the service (that is, non-payment of taxes), and second, the doctrine ofeminent domain, whereby the "lord of the fee" might take back the estate, provided he makejust compensation. Also existing in a vestigial form is the concept ofescheat, under which an estate of a holder without heirs returns to the ownership of the state.
A side effect of this is that government entities do not pay real estate taxes to other government entities since government entities own the land rather than hold the land. Localities that depend on real estate taxes to provide services are often put at a disadvantage when the state or federal government acquires a piece of land. Sometimes, to mollify local public opinion, the state or federal government may volunteer to makepayments in lieu of taxes to local governments.