adjective \ˈklōzd\

Definition of closed

  1. 1a :  not openb :  enclosedc :  composed entirely of closed tubes or vessels a closed circulatory system

  2. 2a :  forming a self-contained unit allowing no additions closed associationb (1) :  traced by a moving point that returns to an arbitrary starting point closed curve; also :  so formed that every plane section is a closed curve closed surface (2) :  characterized by mathematical elements that when subjected to an operation produce only elements of the same set the set of whole numbers is closed under addition and multiplication (3) :  containing all the limit points of every possible subset a closed interval contains its endpointsc :  characterized by continuous return and reuse of the working substance a closed cooling systemd of a racecourse :  having the same starting and finishing point

  3. 3a :  confined to a few closed membershipb :  excluding participation of outsiders or witnesses :  conducted in strict secrecyc :  rigidly excluding outside influence a closed mind

  4. 4 :  ending in a consonant closed syllable

Examples of closed in a sentence

  1. He looked at me through half-closed eyes.

  2. The store is closed for lunch between 1 and 2 p.m.

  3. The beach is closed this time of night.

  4. These restrooms are closed for cleaning.

  5. The chairman declared the discussion closed and allowed no further speeches.

13th Century

First Known Use of closed

13th century

CLOSED Defined for English Language Learners


adjective \ˈklōzd\

Definition of closed for English Language Learners

  • : covering an opening : having an opening that is covered

  • : not operating or open to the public

  • : having ended : not being worked on anymore

CLOSED Defined for Kids


adjective \ˈklōzd\

Definition of closed for Students

  1. :  not open a closed door

Medical Dictionary


adjective \ˈklōzd\

Medical Definition of closed

  1. 1:  being a complete self-contained system with nothing transferred in or out a closed thermodynamic system

  2. 2a:  covered by unbroken skin a closed fractureb:  not penetrating the skull Closed head injuries result from the force of a blast or a blow in which the skull remains intact but the brain, surrounded by fluid like an egg yolk, gets wrenched or slammed against the skull wall.—Neil Shea, National Geographic, December 2006

  3. 3:  not discharging pathogenic organisms to the outside a case of closed tuberculosis—compare open 2

Law Dictionary



Legal Definition of closed

  1. 1 :  confined to a few closed membership

  2. 2 :  excluding outsiders or witnesses :  conducted in secrecy closed hearings

Seen and Heard

What made you want to look up closed? Please tell us where you read or heard it (including the quote, if possible).


to criticize severely

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