Sodium selenide is primarily used in the synthesis of other selenium-containing compounds, which have applications in various industries. In the field of materials science, it serves as a precursor for the preparation of semiconductors and photoconductors, which are essential components in electronic devices. It is also utilized in the production of glass and ceramics, where it imparts specific optical properties, such as color and transparency. In the pharmaceutical industry, sodium selenide is employed in the development of selenium-based drugs, which are explored for their potential antioxidant and anticancer properties. Additionally, it finds use in organic synthesis as a reagent for introducing selenium into organic molecules, leading to the creation of novel compounds with unique chemical and biological activities.