(algebraic geometry, category theory) An algebraic group that is isomorphic to a subgroup of some general linear group.

(group theory) For given field F and order n, the group of n×n matrices with determinant 1, with the group operations of matrix multiplication and matrix inversion.

(group theory) For given field F and order n, the group of invertible n×n matrices, with the group operation of matrix multiplication.

An advocacy group.

plural of group representation constituency

(Singapore, politics) A type of parliamentary constituency with multiple representatives from the same political group, at least one of whom must be from an ethnic minority.

(military) A military unit of the armed forces which incorporates multiple branches of the military within a single command structure (also known as combined arms).

(algebraic geometry) A group which is an analogue for schemes of the fundamental group for topological spaces.

(dated, psychotherapy) A small encounter group meeting in a private home.

(astronomy) A collection of galaxies designated as published by Paul Hickson in 1982.