- not open; shut: a closed door
- covered over or enclosed: a closed wagon
- functioning independently; self-sufficient: a closed economic system
- not receptive to new or different ideas: a closed mind
- not open to further analysis or debate: a closed question
- restricted to certain individuals; exclusive: a closed society
- not open to the public or to nonmembers: a closed meeting
- of or pertaining to a curve with no end points
- of a surface whose plane sections are closed curves
- of a set in which an operation on pairs of its elements always produces an element of the set
- of a set of points containing all its limit points, as the set of points on and within a circle: complementary to an open set
- Phonet. ending in a consonant sound: said of a syllable
- Sports designating a stance, as of a golfer or of a batter in baseball, in which the front foot is closer than the rear foot to an imaginary straight line, as one joining tee and green or one joining home plate and second base
- Having boundaries; enclosed: a closed corridor between the two buildings.
- Blocked or barred to passage or entry: a closed port.
- Explicitly limited; restricted: closed membership.
- Self-contained or self-sufficient: a closed relationship.
- Barred to the public; conducted in secrecy: a closed session of the judiciary committee.
- Mathematics a. Of or relating to a curve, such as a circle, having no endpoints.b. Of or relating to a surface having no boundary curves.c. Of or relating to an interval containing both its endpoints.d. Characterized by or possessing the property by which an operation acting on an element in a set produces an element within the set.
- Computers Of or relating to a file that cannot be accessed.
- Electricity Allowing electricity to flow or pass: a closed switch.
- Linguistics Ending in a consonant: a closed syllable.
- Sports a. Having the forward foot closer to the intended point of impact with the ball than the rear foot: a closed batting stance.b. 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: The club face was closed when it hit the ball, causing a hook.
- Physics a. Of or relating to a closed system.b. Of or relating to a closed universe.
- Sealed, made inaccessible or impassable; not open
- (of a store or business) Not operating or conducting trade
- Not public.
- closed source
- a closed committee
- (topology, of a set) Having an open complement.
- (mathematics, of a set) Such that its image under the specified operation is contained in it.
- The set of integers is closed under addition: .
- (mathematics, logic, of a formula) Lacking a free variable.
- simple past tense and past participle of close