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me·di·an (mēdē-ən)
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adj.
1. Relating to, located in, or extending toward the middle.
2. Anatomy Of, relating to, or situated in or near the plane that divides a bilaterally symmetrical animal into right and left halves; mesial.
3. Statistics Relating to or constituting the middle value in a distribution.
n.
1. A median point, plane, line, or part.
2. The dividing area, either paved or landscaped, between opposing lanes of traffic on some highways. Also called regionally boulevard, mall, median strip, meridian, neutral ground.
3. Statistics The middle value in a distribution, above and below which lie an equal number of values.
4. Mathematics
a. A line that joins a vertex of a triangle to the midpoint of the opposite side.
b. The line that joins the midpoints of the nonparallel sides of a trapezoid.
[Latin mediānus, from medius, middle; see medhyo- in the Appendix of Indo-European roots.]
medi·an·ly adv.
(click for a larger image)
median
(click for a larger image)
median
top:three medians of a triangle and the median of a trapezoid
bottom: highway median
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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