An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

Two line segments if they have the same length. They need not lie at the same angle or position on the plane.

→ congruent; → line; → segment.

1) Of a line, that portion bounded by two points.
2) Of a circle, that portion of a plane bounded by an arc of the circle and its chord.
3) Of a sphere, the solid formed between two parallel planes that cut through a sphere.
4) In computer science, a portion of a program, often one that can be loaded and executed independently of other portions.

From L. segmentum "a strip or piece cut off," originally a geometric term, from secare "to cut" + -mentum "-ment."

Borank, from Kermâni borang "a slice (of fruit);" Borujerdi boleng "piece, section," ultimately from *brin-ka- (probable contracted forms Lari peng and pengi "portion or part of anything"), related to boridan "to cut off;" Mid.Pers. brīn-, blyn-, britan, brinitan "to cut off," Av. brī- "to shave, shear," brin- (with prefix pairi-); cf. Skt. bhrī- "to hurt, injure," bhrinanti "they hurt;" PIE base bhrei- "to cut, pierce."

A large telescope mirror consisting of smaller mirror segments designed to act as a single, larger reflecting surface. Because current monolithic mirrors cannot be constructed larger than about eight meters in diameter, the use of segmented mirrors is a key component for larger aperture telescopes.

Segmented, p.p. of → segment (v.); → mirror.