Dominium - Ownership
There were four fundamental types of dominium in land and resources:
usufructory dominium; and
Under the concept of full private absolute ownership, or absolutum et directum dominium, a plot of land could be established as the exclusive private property of a family patriarch. In other than times of war, when Rome was placed under a the martial law of a dictator, the absolute right to use private property was vested in the patriarch, subject only to dominium eminens (eminent domain or ultimate right of state/community use, conditional upon genuine public necessity and payment of compensation to the domini.) It was the ultimate right of the state, in cases of peril or emergency, to convert the property of individuals to public use. It was also the acknowledged right of individuals, (under dire necessity or emergency,) to commit a trespass (injury or use) on the properties of others, subject to compensation to the owner. Eminent domain defined the proprietal limits of the residual of dominium in the state and the community superior to the individual's exclusive right of use.
Property held in dominium could also be burdened with various servitudes, such as rights of way, right to draw water, or dig sand or lime.
Nudum dominium (naked title) is property ownership of title alone, who someone else has dominium over all the practical rights enabling them to hold and make use of the thing;
Usufructuary dominium (usucapio "taking by use") is property ownership of the right to reasonable use of a thing, without owning the thing itself. Such ownership may occur when the thing is incapable of being reduced to possession by nature. An example of this is the right to use water in a running stream, where the "corpus" or actual body of flowing water precludes the acts of control required by a person to reduce it to ownership.
Dominium utile was ownership as between landlord and tenant.
It should also be noted that another common form of ownership existed outside of dominium known as "possessio," an intermediate or potential ownership associated with the right to use property. Contrasted with usufructory dominium, the ownership status of possessio stemmed either from an imperfect transfer (legal conveyance) of ownership, or from tenantry on the ager publicus (public lands) as "possessore" (possessor) but not domini (owner.) Generally, this prescriptive right became dominium through usucapion and could no longer be questioned after two years of unchallenged occupancy.