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seg·ment (sĕgmənt)
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n.
1. Any of the parts into which something can be divided: segments of the community; a segment of a television program.
2. Mathematics
a. The portion of a line between any two points on the line.
b. The area bounded by a chord and the arc of a curve subtended by the chord.
c. The portion of a sphere cut off by two parallel planes.
3. Biology A clearly differentiated subdivision of an organism or part, such as a metamere.
tr. & intr.v. (sĕg-mĕnt) seg·ment·ed, seg·ment·ing, seg·ments
To divide or become divided into segments.
[Latin segmentum, from secāre, to cut; see sek- in the Appendix of Indo-European roots.]
segmen·tar′y (-mən-tĕr′ē) adj.
(click for a larger image)
segment
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. 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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