the.com/fence

means A barrier of posts, wire, or wood that marks a boundary or encloses an area — or, as a verb, to enclose with one (or to deal in stolen goods, or to duel with swords).

from From Middle English 'fens,' a clipped form of 'defens' — the same root that gives us 'defense,' from Latin 'defendere,' to ward off. A fence began life as a shortening of 'defense,' literally a thing that defends a piece of ground. The 'stolen goods' sense, which surfaced in thieves' slang centuries later, plays on the idea of a fence as a protective screen — a buyer who shields a thief from being caught.