1. The act of relaxing or the state of being relaxed.
2. Refreshment of body or mind; recreation: played golf for relaxation.
3. A loosening or slackening.
4. A reduction in strictness or severity.
5. Physiology The lengthening of inactive muscle or muscle fibers.
6. Physics The return or adjustment of a system to equilibrium following displacement or abrupt change.
7. Mathematics A method of solving equations in which the errors resulting from an initial approximation are reduced by succeeding approximations until all errors are within specified limits.
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:
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.