Land or things attached to land;
real property or
real estate.
A term not entirely foreign to the common law but recognized as issue from Roman law and its offspring, the civil law. Indeed, a well-known Latin maxim: solo cedit, quicquid solo plantatur (what is affixed to the soil belongs to the soil).
Refers to, as John Bouvier set out:
"Property which, from its nature, destination or the object to which it is applied, cannot move itself or be removed."

The Quebec
Civil Code defines
immovables initially using surprisingly simple language but then, as the sections progress with the clear intent to fully codify the law, clarity breaks down (§899-907; with some editing). Nonetheless, the similarities with the
common law of
fixtures and
quicquid plantatur solo, solo cedit are striking:
"Property ... is divided into immovables and movables.
"Land, and any constructions and works of a permanent nature located thereon and anything forming an integral part thereof, are immovables.
"Plants and minerals, as long as they are not separated or extracted from the land, are also immovables. Fruits and other products of the soil may be considered to be movables, however, when they are the object of an act of alienation (sale).
"Movables incorporated with an immovable that lose their individuality and ensure the utility of the immovable form an integral part of the immovable (and) integral parts of an immovable that are temporarily detached therefrom retain their immovable character if they are destined to be put back.
"Movables which are permanently physically attached or joined to an immovable without losing their individuality and without being incorporated with the immovable are immovables for as long as they remain there.
"Real (property) rights in immovables, as well as actions to assert such rights or to obtain possession of immovables, are immovables.
"Things which can be moved either by themselves or by an extrinsic force are movables.
"Waves or energy harnessed and put to use by man, whether their source is movable or immovable, are deemed ... movables.
"All other property, if not qualified by law, is movable."
In Louisiana Civil Code, immovables are defined as:
"... tracts of land, with their component parts.
"Buildings, other constructions permanently attached to the ground, standing timber, and unharvested crops or ungathered fruits of trees, are component parts of a tract of land when they belong to the owner of the ground.
"Things incorporated into a tract of land, a building, or other construction, so as to become an integral part of it, such as building materials, are its component parts."
REFERENCES:
- Bouvier, John, Bouvier's Law Dictionary (Boston: The Boston Book Company, 1897), p. 984.
- Duhaime, Lloyd, Legal Definition of Movable
- Louisiana Civil Code, published at legis.state.la.us/
- Quebec Civil Code, L. Q. 1991, Chapter 64, published at canlii.org/qc/laws/sta/ccq/