Homonym: Trivalent (Valency)
Trivalent refers to a chemical species that has a valence of three, meaning it can form three bonds with other atoms. This term is often used in chemistry to describe certain elements or compounds, such as trivalent metals like aluminum or iron, which can participate in various chemical reactions due to their ability to bond with three other atoms or ions.
In the context of immunology, trivalent can describe vaccines that contain three different antigens to protect against multiple strains of a virus. For example, a trivalent influenza vaccine targets three specific strains of the influenza virus, enhancing the immune response and providing broader protection during flu season.