"A posteriori" is a Latin term meaning "from the latter." It refers to knowledge or justification that is dependent on empirical evidence or experience. In philosophy, it contrasts with "a priori," which is knowledge that can be gained independently of experience. For example, scientific observations and experiments often rely on a posteriori reasoning. In everyday life, a posteriori knowledge can be seen in how we learn from our experiences. For instance, if you touch a hot stove and get burned, you learn that stoves can be hot through direct experience. This type of knowledge is essential in fields like science and empirical research.