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sec·tion (sĕkshən)
1. One of several components; a piece.
2. A subdivision of a written work.
3. Law A distinct portion or provision of a legal code or set of laws, often establishing a particular legal requirement: section 5 of the Voting Rights Act.
4. A distinct portion of a newspaper: the sports section.
5. A distinct area of a town, county, or country: a residential section.
6. A land unit equal to one square mile (2.59 square kilometers), 640 acres, or 1/36 of a township.
7. The act or process of separating or cutting, especially the surgical cutting or dividing of tissue.
8. A thin slice, as of tissue, suitable for microscopic examination.
9. A segment of a fruit, especially a citrus fruit.
10. Representation of a solid object as it would appear if cut by an intersecting plane, so that the internal structure is displayed.
11. Music A group of instruments or voices in the same class considered as a division of a band, orchestra, or choir: the rhythm section; the woodwind section.
12. A class or discussion group of students taking the same course: She taught three sections of English composition.
a. A portion of railroad track maintained by a single crew.
b. An area in a train's sleeping car containing an upper and lower berth.
14. An army tactical unit smaller than a platoon and larger than a squad.
15. A unit of vessels or aircraft within a division of armed forces.
16. One of two or more vehicles, such as a bus or train, given the same route and schedule, often used to carry extra passengers.
a. The character (§) used in printing to mark the beginning of a section.
b. This character used as the fourth in a series of reference marks for footnotes.
18. Informal A cesarean section.
tr.v. sec·tioned, sec·tion·ing, sec·tions
1. To separate or divide into parts.
2. To cut or divide (tissue) surgically.
3. To shade or crosshatch (part of a drawing) to indicate sections.
4. Informal To perform a cesarean section on.

[Middle English seccioun, from Old French, from Latin sectiō, sectiōn-, from sectus, past participle of secāre, to cut; see sek- in the Appendix of Indo-European roots.]

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.