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tol·er·ance (tŏlər-əns)
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n.
1. The capacity for or the practice of recognizing and respecting the beliefs or practices of others.
2.
a. Leeway for variation from a standard.
b. The permissible deviation from a specified value of a structural dimension, often expressed as a percent.
3. The capacity to endure hardship or pain.
4.
a. Physiological resistance to a toxin.
b. Diminution in the physiological response to a drug that occurs after continued use, necessitating larger doses to produce a given response.
c. The ability to digest or metabolize a food, drug, or other substance or compound: glucose tolerance.
5.
a. Acceptance of a tissue graft or transplant without immunological rejection.
b. Unresponsiveness to an antigen that normally produces an immunologic reaction.
6. The ability of an organism to resist or survive infection by a parasitic or pathogenic organism.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. 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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