Spillovers are commonly referred to as the unintended or secondary effects resulting from a primary activity or process. Alternative synonyms to spillovers include "externalities," which refers to the economic effects of a product or service that fall on parties other than the producer or consumers, and "ripple effects," which refers to the cascading or domino-like effect of an action through various interconnected systems. Another synonym often used to describe spillovers is "consequences." This term emphasizes the subsequent results of an initial action or process, rather than the primary outcome. Other related terms include "knock-on effects," "contagion," and "domestic externalities.