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noun ca·pac·i·ty \kə-ˈpa-sə-tē, -ˈpas-tē\

Simple Definition of capacity

  • : the ability to hold or contain people or things

  • : the largest amount or number that can be held or contained

  • : the ability to do something : a mental, emotional, or physical ability

Source: Merriam-Webster's Learner's Dictionary

Full Definition of capacity

plural capacities

  1. 1 :  legal competency or fitness <capacity to stand trial>

  2. 2 a :  the potential or suitability for holding, storing, or accommodating <a large seating capacity> b :  the maximum amount or number that can be contained or accommodated <a jug with a one-gallon capacity> <the auditorium was filled to capacity> — see metric system table, weight table

  3. 3 a :  an individual's mental or physical ability :  aptitude, skill b :  the faculty or potential for treating, experiencing, or appreciating <capacity for love>

  4. 4 :  duty, position, role <will be happy to serve in any capacity>

  5. 5 :  the facility or power to produce, perform, or deploy :  capability <a plan to double the factory's capacity>; also :  maximum output <industries running at three-quarter capacity>

  6. 6 a :  capacitance b :  the quantity of electricity that a battery can deliver under specified conditions

Examples of capacity in a sentence

  1. The nightclub has a 1,000-person capacity.

  2. a bottle with a capacity of two liters

  3. Does he have the capacity to handle this job?

  4. The disease causes a deterioration of breathing capacity.

  5. He was acting in his capacity as judge.

  6. serving in a supervisory capacity

Origin of capacity

Middle English capacite, from Middle French capacité, from Latin capacitat-, capacitas, from capac-, capax

First Known Use: 15th century



adjective ca·pac·i·ty

Definition of capacity

  1. :  equaling maximum capacity <a capacity crowd>


First Known Use of capacity


CAPACITY Defined for Kids


noun ca·pac·i·ty \kə-ˈpa-sə-tē\

Definition of capacity for Students

plural capacities

  1. 1 :  ability to contain or deal with something <The room has a large seating capacity.> <Factories are working to capacity.>

  2. 2 :  mental or physical power <You have the capacity to do better.>

  3. 3 :  volume 3 <The tank has a ten-gallon capacity.>

  4. 4 :  role 1, status <In your capacity as team captain, you can set a good example.>

Medical Dictionary


noun ca·pac·i·ty \kə-ˈpas-ət-ē, -ˈpas-tē\

Medical Definition of capacity

plural capacities

  1. 1a:  the ability to hold, receive, store, or accommodateb:  a measure of content :  the measured ability to contain :  volume <a beaker with a capacity of one liter>—see vital capacityc (1):  capacitance (2):  the quantity of electricity that a battery can deliver under specified conditions

  2. 2:  legal qualification, competency, power, or fitness

  3. 3a:  power to grasp and analyze ideas and cope with problemsb:  blended power, strength, and ability <encourage physical activity to the limit of the child's capacity—Morris Fishbein>

Law Dictionary


noun ca·pac·i·ty

Legal Definition of capacity

plural capacities

  1. 1 :  a qualification, power, or ability (as to give consent or make a testament) created by operation of law

  2. 2 :  an individual's ability or aptitude; especially :  mental ability as it relates to responsibility for the commission of a crime (as murder) — see also diminished capacity — compare competency, incapacity, insanity

Seen and Heard

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expressing little or no emotion

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