noun a self-contained part of a larger composition (written or musical)
Synonymssubdivision
noun one of several parts or pieces that fit with others to constitute a whole object
Synonymssegment
noun one of the portions into which something is regarded as divided and which together constitute a whole
noun (geometry) the area created by a plane cutting through a solid
Synonymsplane section
noun a small class of students who are part of a larger course but are taught separately
Synonymsdiscussion section
noun a specialized division of a large organization
Synonymsdepartment
noun the cutting of or into body tissues or organs (especially by a surgeon as part of an operation)
verb divide into segments
Synonymssegment
Source: WordNet 3.1, Princeton University