adjective

• Sealed, made inaccessible or impassable; not open.
• (engineering, gas and liquid flow, of valve or damper) To be in a position preventing fluid from flowing.
• (electricity, of a switch or circuit breaker) To be in a position allowing electricity to flow.
• (of a store or business) Not operating or conducting trade.
• Not public.
• (topology, of a set) Having an open complement.
• (mathematics, of a set) Such that its image under the specified operation is contained in it.
• (mathematics, logic, of a formula) Lacking a free variable.
• (graph theory, of a walk) Whose first and last vertices are the same, forming a closed loop.
• (phonology) Formed by closing the mouth and nose passages completely, like the consonants /t/, /d/, and /p/.
• (phonology) Having the sound cut off sharply by a following consonant, like the /ɪ/ in pin.
• (of a multi-word compound) Having component words joined together without spaces or hyphens; for example, timeslot as opposed to time slot or time-slot.