seg·ment 
(sĕgmənt)
(sĕgmənt)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.
segment