Enclose, envelop, fence, pen, coop, corral, cage, wall mean to surround so as to shut in or confine actually or apparently.
Enclose implies a shutting in by barriers (as walls) or in an enveloping cover (as a case); the term may be used without connotations, or it may suggest protection, defense, privacy, or monastic seclusion.
Envelop (see also COVER ) implies enclosure in or by something usually yielding or penetrable that surrounds it on all sides and serves to screen it, to protect it, or to separate it from others.
Fence in this sense is usually followed by in or about and means only to enclose with or as if with a fence (as by a row of palings, a wall, or a hedge); the term usually connotes a means of barring trespassers, of keeping animals from wandering about or intruding, or of securing privacy.
In extended use the term is a synonym of enclose only when that by which a thing is shut in is a man-made limitation.
Pen, usually followed by up or in, implies confinement in or as if in an enclosure with narrow limits and suggests irksome restraint.
Coop, usually followed by up, also implies confinement in a limited enclosure but it carries even a stronger implication of cramping limitations.
Corral implies a shutting up in or as if in a strongly fenced enclosure and is used primarily of animals or persons who would scatter, escape, or flee if not securely confined.
In extended use corral may largely lose its basic notion of shutting up and stress, rather, the difficulty of catching or bringing under control.
Cage is often used, especially with in or up, to imply confinement with severe or humiliating restrictions.
Wall means enclosed by a wall which may be material or may be made up of harsh or rigid and impenetrable restraints.