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su·per·po·si·tion (s′pər-pə-zĭshən)
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n.
1. The act of superposing or the state of being superposed: "Yet another technique in the forensic specialist's repertoire is photo superposition" (Patrick Nuyghe).
2. Geology The principle that in a group of stratified sedimentary rocks the lowest were the earliest to be deposited.
3. Physics The combination of two or more physical states, such as waves, to form a new physical state in accordance with the superposition principle.
tr.v. su·per·po·si·tioned, su·per·po·si·tion·ing, su·per·po·si·tions
To superpose.
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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