the pure mathematics of points and lines and curves and surfaces
"The course focused on geometry as the pure mathematics of points, lines, and curves rather than practical surveying techniques."
The branch of mathematics dealing with spatial relationships.
"Geometry is the branch of mathematics that studies shapes and their spatial relationships in space."
In plain English: Geometry is the branch of math that studies shapes, sizes, and how they fit together in space.
"The children spent their afternoon learning how to draw basic shapes in geometry class."
Usage: Geometry focuses on shapes, sizes, and positions in space rather than numerical calculations like arithmetic or algebra. Use this term when discussing properties such as angles, lines, circles, and three-dimensional figures.
From Middle English gemetry, geometrie, from Old French geometrie (modern French géométrie), from Latin geōmetria, from Ancient Greek γεωμετρία (geōmetría, "geometry, land-survey"), from γεωμέτρης (geōmétrēs, "geometer, land measurer"), from γῆ (gê, "earth, land, country") + -μετρία (-metría, "measurement"), from μέτρον (métron, "a measure"). By surface analysis, geometer + -y or geo- + -metry. Doublet of gematria.