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1. Maths
a. a part of a line or curve between two points
b. a part of a plane or solid figure cut off by an intersecting line, plane, or planes, esp one between a chord and an arc of a circle
2. Zoology any of the parts into which the body or appendages of an annelid or arthropod are divided
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



in mathematics. A segment of a line is the set of points on the line that are located between two points A and B; in Russian usage, the segment includes both A and B. In other words, a segment is the set of points of a line such that the coordinates of the points satisfy the condition axb, where a and b are the coordinates of the segment endpoints. Thus, the segment constitutes a closed interval and can be denoted by [a, b].



(1)A segment in the plane is a region bounded by a chord and the arc of the curve subtended by the chord. The area of the segment AmB of the circle in Figure 1 is the difference between the area of the sector OAmB and the triangle OAB.

Figure 1

(2) A segment in space is a part cut off from a solid by a plane. An example is a spherical segment.

(3) A segment of a line is the set of points on a line that are located between two points A and B. In Russian usage, the two points A and B are included in the segment. Thus, a segment is the set of points on a line whose coordinates satisfy the condition axb. (SeeINTERVAL AND SEGMENT.)



(also metamere), one of a series of homologous parts of the body of an animal, located along the long axis of the body. Segments may be similar to one another; for instance, among the most primitive annelids the entire complex of organs is repeated in each segment. Given the same general structure, complete similarity between segments may be destroyed by the absence of certain organs or by some change in the organs: these types of segments may be observed among arthropods. The segmentation of an animal’s body is also called metamerism.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


(analytical chemistry)
A specific, demarcated portion of a lot of a substance that is to be chemically analyzed.
(computer science)
A single section of an overlay program structure, which can be loaded into the main memory when and as needed.
In some direct-access storage devices, a hardware-defined portion of a track having fixed data capacity.
A segment of a line or curve is any connected piece.
A segment of a circle is a portion of the circle bounded by a chord and an arc subtended by the chord.
A segment of a totally ordered Abelian group G is a subset D of G such that if a is in D then so are all elements b satisfying -aba.
In air operations, a basic functional division of an instrument approach procedure; it bears a fixed orientation with respect to the course to be flown; it is assigned specific geometric coordinates which uniquely determine its position; the location of the segment is assigned with respect to the obstacles in the operations area.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


/seg'ment/ 1. <architecture> A collection of pages in a memory management system.

2. <programming> A separately relocatable section of an executable program. Unix executables have a text segment (executable machine instructions), a data segment (initialised data) and a bss segment (uninitialised data).

3. <networking> network segment.

4. To experience a segmentation fault. Confusingly, the stress is often put on the first syllable, like the noun "segment", rather than the second like mainstream verb "segment". This is because it is actually a noun shorthand that has been verbed.

5. A block of memory in a segmented address space.
This article is provided by FOLDOC - Free Online Dictionary of Computing (


(1) Any partition, reserved area, partial component or piece of a larger structure. See overlay.

(2) One of the bars that make up a single character in an LED or LCD display.

(3) For DOS segment addressing, see paragraph.
Copyright © 1981-2019 by The Computer Language Company Inc. All Rights reserved. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction is strictly prohibited without permission from the publisher.
References in periodicals archive ?
Mastropasqua, "Anterior segment optical coherence tomography imaging of conjunctival filtering blebs after glaucoma surgery," BioMed Research International, vol.
It prevents cystoid macular oedema, retinal detachment and anterior segment neovascularisation.1,17 Stability of IOL position was also an important problem after Nd:YAG laser capsulotomy for unexpected visual problems.
Anterior segment optical coherence tomography- guided management algorithm for Descemet membrane detachment after intraocular surgery.
Dr Agarwals' Textbook on Corneal Topography Including Pentacam and Anterior Segment OCT.
(18,19) These posterior segment differences suggested the possibility of anterior segment alterations in juvenile glaucoma patients.
In accordance to present study, Holman et al.19 achieved more than 85 percent corrections in upper anterior segment, over jet and midline in extraction and non extraction groups.
Thus, further prospective studies with and without cycloplegia are still needed to clarify the effects of accommodation on the dimensions of the anterior segment before and after surgery.
Though I would say that the image is of lower quality than for the anterior segment images, I can record peripheral fundus abnormalities occurring outside the normal field of view of a conventional fundus camera.
INTRODUCTION: Toxic Anterior Segment Syndrome (TASS) is acute, non-infectious, sterile inflammation affecting the anterior segment of eye ball.
Boyd et al., ophthalmologists from Panama, Italy, and the US, bring together a group of ophthalmologists from India, the US, South America, and Europe for 19 chapters on optical coherence tomography (OCT) and its uses and interpretation and applications in ophthalmology, including in the anterior segment and retina, and in the diagnosis and management of glaucoma and age-related macular degeneration.
This new and advancing technology holds promise for accurate and fast diagnosis of conditions of the cornea and anterior segment of the eye and also for preoperative and postoperative evaluation because it offers high-resolution imagery, in cross-sectional and three-dimensional views.

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