What is Fence?

Legal Definition
A fence is a structure that encloses an area, typically outdoors, and is usually constructed from posts that are connected by boards, wire, rails or netting. A fence differs from a wall in not having a solid foundation along its whole length.

Alternatives to fencing include a ditch (sometimes filled with water, forming a moat).
-- Wikipedia
Legal Definition
A building or erection between two contiguous estates, so as to divide them; or on the same estate, so as to divide one part from another.

2. Fences are regulated by the local laws. In general, fences on boundaries are to be built on the line, and the expense, when made no more expensively than is required by the law, is borne equally between the parties. See the following cases on the subject. 2 Miles, 337, 395; 2 Greenl. 72; 11 Mass. 294; 3 Wend. 142; 2 Metc. 180; 15 Conn. 526 2 Miles, 447; Bouv. Inst. Index, h. t.

3. A partition fence is presumed to be the common property of both owners of the land. 8 B. & C. 257, 259, note a. When built upon the land of one of them, it is his; but if it were built equally upon the land of both, at their joint expense, each would be the owner in severalty of the part standing on his own land. 5 Taunt. 20; 2 Greenl. Ev. 617.
-- Bouviers Law Dictionary
Legal Definition
v. In old Scotch law. To defend or protect by formalities. To "fence a court" was to open it in due form, and interdict all manner of persons from disturbing their proceedings. This was called "fencing," q. d., defending or protecting the court
-- Black's Law Dictionary
Legal Definition
n. A hedge, structure or partition, erected for the purpose of inclosing a piece of land or to divide a piece of land into distinct portions or to separate two contiguous estates. See Kimball v. Carter, 95 Va. 77, 27 S. E. 823, 38 L R. A. 570; Estes v. Railroad Co., 63 Me. 309; Allen v. Tobias, 77 111. 171.
-- Black's Law Dictionary
Legal Definition
An enclosure; a defense; a place where stolen goods are received; the keeper of such a place; to deliver stolen goods at such a place; to try to evade questions in giving testimony.
-- Ballentine's Law Dictionary