Segment gear

Segment Seg"ment, n. [L. segmentum, fr. secare to cut, cut off: cf. F. segment. See {Saw} a cutting instrument.] 1. One of the parts into which any body naturally separates or is divided; a part divided or cut off; a section; a portion; as, a segment of an orange; a segment of a compound or divided leaf. [1913 Webster]

2. (Geom.) A part cut off from a figure by a line or plane; especially, that part of a circle contained between a chord and an arc of that circle, or so much of the circle as is cut off by the chord; as, the segment acb in the Illustration. [1913 Webster]

3. (Mach.) (a) A piece in the form of the sector of a circle, or part of a ring; as, the segment of a sectional fly wheel or flywheel rim. (b) A segment gear. [1913 Webster]

4. (Biol.) (a) One of the cells or division formed by segmentation, as in egg cleavage or in fissiparous cell formation. (b) One of the divisions, rings, or joints into which many animal bodies are divided; a somite; a metamere; a somatome. [1913 Webster]

{Segment gear}, a piece for receiving or communicating reciprocating motion from or to a cogwheel, consisting of a sector of a circular gear, or ring, having cogs on the periphery, or face.

{Segment of a line}, the part of a line contained between two points on it.

{Segment of a sphere}, the part of a sphere cut off by a plane, or included between two parallel planes.

{Ventral segment}. (Acoustics) See {Loor}, n., 5. [1913 Webster]