geometry

n. mathematical study of lines and points and angles

Geometry (Greek γεωμετρία; geo = earth, metria = measure) is a part of mathematics concerned with questions of size, shape, and relative position of figures and with properties of space. Geometry is one of the oldest sciences. Initially a body of practical knowledge concerning lengths, areas, and volumes, in the third century B.C. geometry was put into an axiomatic form by Euclid, whose treatment set a standard for many centuries to follow. Astronomy served as an important source of geometric problems during the next one and a half millennia.
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(n.)
That branch of mathematics which investigates the relations, properties, and measurement of solids, surfaces, lines, and angles; the science which treats of the properties and relations of magnitudes; the science of the relations of space.
  

(n.)
A treatise on this science.
  

orthogonal 

Noun
1. the pure mathematics of points and lines and curves and surfaces
(hypernym) pure mathematics
(hyponym) affine geometry
(classification) mathematics, math, maths
(class) congruent