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Me·rid·i·an (mə-rĭdē-ən)
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A city of eastern Mississippi near the Alabama border east of Jackson. A confederate base during the Civil War, it developed as a railroad junction.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
me·rid·i·an (mə-ride-ən)
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n.
1.
a. An imaginary great circle on the earth's surface passing through the North and South geographic poles.
b. Either half of such a great circle from pole to pole. All points on the same meridian have the same longitude.
2. Astronomy A great circle passing through the two poles of the celestial sphere and the zenith of a given observer.Also called celestial meridian, local meridian, vertical circle.
3. Mathematics
a. A curve on a surface of revolution, formed by the intersection of the surface with a plane containing the axis of revolution.
b. A plane section of a surface of revolution containing the axis of revolution.
4. Any of the longitudinal lines or pathways on the body along which the acupuncture points are distributed.
5. Archaic
a. The highest point in the sky reached by the sun or another celestial body; a zenith.
b. The time at which the sun reaches its highest point in the sky; noon.
6. The highest point or stage of development; peak:"Men come to their meridian at various periods of their lives"(John Henry Newman).
7. Midwestern US See median.
adj.
1. Of or relating to a meridian; meridional.
2. Of or at midday:the meridian hour.
3. Of, relating to, or constituting the highest point, as of development or power:the empire in its meridian period.

[Middle English, fromOld French, midday, fromLatinmeridiānus, of midday, frommeridies, midday, frommeridie, at midday, alteration ofearlier*medidie, from*mediei die : *mediei, dative (locative) ofmedius, middle; see medhyo- in the Appendix of Indo-European roots + die, dative ofdies, day; see dyeu- in the Appendix of Indo-European roots.]
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meridian

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 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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