Is chirality synonymus with optical activity?

Chirality and optical activity are related concepts, but they are not synonymous. Chirality refers to the geometric property of a molecule having a non-superimposable mirror image, typically due to the presence of a chiral center. Optical activity, on the other hand, is the ability of chiral molecules to rotate the plane of polarized light. While all optically active substances are chiral, not all chiral substances exhibit optical activity under certain conditions, such as when they are present in racemic mixtures.