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in·ver·sion (ĭn-vûrzhən)
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n.
1.
a. The act of inverting.
b. The state of being inverted.
2. An interchange of position of adjacent objects in a sequence, especially a change in normal word order, such as the placement of a verb before its subject.
3. Music
a. A rearrangement of tones in which the upper and lower voices of a melody are transposed, as in counterpoint.
b. A rearrangement of tones in which each interval in a single melody is applied in the opposite direction.
c. An arrangement of the tones of a chord such that the root is not the lowest pitch, as in the rearrangement of the C-major triad CEG to EGC.
4. Psychology In early psychology, behavior or attitudes in an individual considered typical of the opposite sex, including sexual attraction to members of one's own sex. No longer in scientific use.
5. Chemistry Conversion of a substance in which the direction of optical rotation is reversed, from the dextrorotatory to the levorotatory or from the levorotatory to the dextrorotatory form.
6. Meteorology An atmospheric condition in which the air temperature rises with increasing altitude, holding surface air down and preventing dispersion of pollutants.
7. Genetics A chromosomal rearrangement in which a segment of the chromosome breaks off and reattaches in the reverse direction.

[Latin inversiō, inversiōn-, from inversus, past participle of invertere, to invert; see INVERT.]

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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