1
a
: not open
b
c
: composed entirely of closed tubes or vessels
a closed circulatory system
2
a
: having the skin intact with no underlying tissue exposed
closed wounds
see also closed fracture
b
of a head injury : having the skull intact : not marked by fracture or penetration of the skull
3
a
: forming a self-contained unit allowing no additions
closed association
b(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 endpoints
c
: characterized by continuous return and reuse of the working substance
a closed cooling system
d
of a racecourse : having the same starting and finishing point
4
a
: confined to a few
closed membership
b
: excluding participation of outsiders or witnesses : conducted in strict secrecy
c
: rigidly excluding outside influence
a closed mind
5
: ending in a consonant
closed syllable

Examples of closed in a Sentence

He looked at me through half-closed eyes. The store is closed for lunch between 1 and 2 p.m. The beach is closed this time of night. These restrooms are closed for cleaning. The chairman declared the discussion closed and allowed no further speeches.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Ryals agrees and adds that closed storage will help eliminate breaking, too. Nicole Letts, Southern Living, 14 Dec. 2024 The penal colonies of French Guiana were finally, permanently closed in 1953; their remains are now a macabre tourist attraction for the few visitors that make it to Cayenne. Rob Crossan, JSTOR Daily, 13 Dec. 2024 On Thursday, the Swedish Prosecution Authority released a statement confirming the investigation was now closed, without naming any individuals involved. Ben Church, CNN, 12 Dec. 2024 Tech companies have posited that their material is open sourced and comes from publicly accessible data, but the dialogue that powers some of the models is often drawn from closed captions on YouTube videos and other sources rather than the original source material directly. Brian Welk, IndieWire, 12 Dec. 2024 See all Example Sentences for closed 

Word History

First Known Use

13th century, in the meaning defined at sense 1a

Time Traveler
The first known use of closed was in the 13th century

Dictionary Entries Near closed

Cite this Entry

“Closed.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/closed. Accessed 22 Dec. 2024.

Kids Definition

closed

adjective
1
a
: not open : enclosed
b
: made up entirely of closed tubes or vessels
a closed circulatory system
2
: formed by a line that returns to its starting point
a closed curve
3
: having elements that when a mathematical operation (as addition) is performed on them produce only other elements of the same set
the set of whole numbers is closed under addition
4
: not admitting or not easily admitting new members
a closed meeting
a closed society

Medical Definition

closed

adjective
1
: being a complete self-contained system with nothing transferred in or out
a closed thermodynamic system
2
a
: having the skin intact with no underlying tissue exposed
closed wounds
see closed fracture
b
of a head injury : having the skull intact : not marked by fracture or penetration of 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
3
: not discharging pathogenic organisms to the outside
a case of closed tuberculosis
compare open entry 1 sense 2

Legal Definition

closed

adjective
1
: confined to a few
closed membership
2
: excluding outsiders or witnesses : conducted in secrecy
closed hearings
Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!