closed

from The American Heritage® Dictionary of the English Language, 5th Edition.

• adjective Having boundaries; enclosed.
• adjective Blocked or barred to passage or entry.
• adjective Explicitly limited; restricted.
• adjective Self-contained or self-sufficient.
• adjective Barred to the public; conducted in secrecy.
• adjective Of or relating to a curve, such as a circle, having no endpoints.
• adjective Of or relating to a surface having no boundary curves.
• adjective Of or relating to an interval containing both its endpoints.
• adjective Characterized by or possessing the property by which an operation acting on an element in a set produces an element within the set.
• adjective Computers Of or relating to a file that cannot be accessed.
• adjective Electricity Allowing electricity to flow or pass.
• adjective Linguistics Ending in a consonant.
• adjective Having the forward foot closer to the intended point of impact with the ball than the rear foot.
• adjective Held or swung with the top or outer edge of the striking face pointing slightly closer to the objective than the lower or inner edge.
• adjective Of or relating to a closed system.
• adjective Of or relating to a closed universe.

from the GNU version of the Collaborative International Dictionary of English.

• adjective having an opening obstructed.
• adjective (Math.) of a curve or surface: having no end points or boundary curves; of a set: having members that can be produced by a specific operation on other members of the same set; of an interval: containing both its endpoints.
• adjective Being in a position to obstruct an opening; -- especially of doors.
• adjective having skin drawn so as to obstruct the opening; -- used of mouth or eyes. Opposite of open.
• adjective prenominal requiring union membership; -- of a workplace.
• adjective closed with shutters.
• adjective hidden from the public.
• adjective not open to the general public.
• adjective unsympathetic; -- of a person's attitude.
• adjective surrounded by walls.
• adjective made compact by bending or doubling over.
• adjective closed or fastened with or as if with buttons.
• adjective not engaged in activity; -- of an organization or business establishment.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• adjective Sealed, made inaccessible or impassable; not open
• adjective of a store or business Not operating or conducting trade
• adjective Non public (as in closed source)
• adjective topology, of a set Having an open complement.
• adjective mathematics, of a set Such that its image under the specified operation is contained in it.
• adjective mathematics, logic Lacking a free variable.
• verb Simple past tense and past participle of close.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• adjective with shutters closed
• adjective not open
• adjective (set theory) of an interval that contains both its endpoints
• adjective not open or affording passage or access
• adjective requiring union membership
• adjective not having an open mind
• adjective blocked against entry
• adjective not open to the general public
• adjective used especially of mouth or eyes