Not to be confused with inversive geometry, in which inversion is through a circle instead of a point. In
geometry, a
point reflection or
inversion in a point (or
inversion through a point, or
central inversion) is a type of
isometry of
Euclidean space. An object that is invariant under a point reflection is said to possess
point symmetry; if it is invariant under point reflection through its center, it is said to possess
central symmetry or to be
centrally symmetric.