(sek′shən) noun
1. A separate part or division; a portion of a book, treatise, or writing; a subdivision of a chapter; also, a division of law.
2. A distinct part of a country, community, etc.
3. U.S. An area of public land one mile square, containing 640 acres and constituting 1/36 of a township.
4. A portion of a railway company's tracks under the care of a particular set of men.
5. In a sleeping–car, a space containing two berths.
6. A tactical unit of the U.S. Army, smaller than a platoon and larger than a squad.
7. A division of an animal group, of indeterminate rank.
8. A representation, picture, or drawing of a building, machine, geological formation, etc., as if cut by an intersecting plane; also, the thing so cut or viewed.
9. A very thin slice of anything, especially for microscopic examination.
10. The character §, indicating a subdivision: used also as a reference mark.
11. The act of cutting; division by cutting, as in surgical operations.
12. The figure formed by the intersection of a plane or other surface with a solid. In mechanical drawing the following sections are distinguished: lengthwise or longitudinal section, usually representing objects as cut lengthwise through the center; cross–section or transverse section, cut crosswise; horizontal section, cut horizontally, and usually through the center; oblique section, cut at various angles. See synonyms under PART.
—frozen section A cutting, slice, or sliced surface of a frozen part: much employed in anatomy.
—v.t.
1. To cut or divide into sections.
2. To shade (a drawing) so as to designate a section or sections. [<MF <L sectio, -onis <sectus, pp. of secare cut]

The act or process of cutting or dividing: vivisection. [<L sectio, -onis a cutting <secare cut]