Ensheath

Ensheathe is a verb meaning to surround or encase something in a protective sheath or covering. A sheath is a covering that provides insulation, containment, or protection from abrasion and environmental exposure. The term is used across disciplines to describe both the act of wrapping and the resulting protective layer.

In biology, ensheathment refers to the wrapping of biological fibers by specialized cells to form a sheath. A common example is the myelin sheath surrounding nerve fibers, produced by Schwann cells in the peripheral nervous system and by oligodendrocytes in the central nervous system. This ensheathment increases conduction velocity and insulates the axon, although gaps known as nodes of Ranvier interrupt the sheath to facilitate saltatory conduction.

In technology and engineering, ensheathment describes enclosing an object with a protective jacket or insulation. Electrical and communication cables often have a polymer or rubber insulation that serves as a sheath, and fiber-optic cables may be encased in protective sheathing to shield against moisture, chemicals, and mechanical stress. The process can involve extrusion, coating, or encapsulation to apply the sheath around the core component.

Other contexts include industrial and environmental applications where components, pipes, or cables are ensheathed to prevent corrosion, contamination, or damage from the surrounding environment. This term emphasizes the transition from an exposed core to a protected, encased form.

See also: sheath, myelin, insulation, coating, encapsulation.