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ca·pac·i·ty (kə-păsĭ-tē)
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n. pl. ca·pac·i·ties
1.
a. The ability to receive, hold, or absorb something: the storage capacity of a car's trunk.
b. The maximum amount that can be contained: a bin filled to capacity.
2. The power to learn or retain knowledge; mental ability.
3.
a. The ability to do, make, or accomplish something; capability: a comedian's capacity for making people laugh.
b. The maximum or optimum amount that can be produced: factories operating below capacity.
4. The quality of being suitable for or receptive to specified treatment: the capacity of elastic to be stretched.
5. The position in which one functions; role: in your capacity as sales manager.
6. Legal qualification or authority: the capacity to make an arrest.
7. Electricity Capacitance.
adj.
Filling a space with the most it can hold: a capacity crowd at the concert.

[Middle English capacite, from Old French, from Latin capācitās, from capāx, capāc-, spacious; see CAPACIOUS.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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