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joule (jl, joul)
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n. Abbr. J or j
The International System unit of electrical, mechanical, and thermal energy, equal to the work done when a force of one newton acts through a distance of one meter, and also equal to the work done when a current of one ampere is passed through a resistance of one ohm for one second.

[After James Prescott Joule.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
Joule (jl, joul), James Prescott 1818-1889.
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British physicist who established the mechanical theory of heat and discovered the first law of thermodynamics.

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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