The term "meso" comes from the Greek word for "middle" and is used in various fields to describe something that is intermediate or in between. In geography, it can refer to the mesosphere, which is the layer of the Earth's atmosphere located between the stratosphere and the thermosphere. In biology, "meso" can describe structures that are in the middle of a hierarchy, such as mesoderm, one of the three primary germ layers in embryonic development. In social sciences, "meso" often refers to the level of analysis that focuses on groups or organizations, bridging the gap between individual behavior and larger societal trends. For example, meso-level analysis might examine how community organizations influence local health outcomes. This middle level helps researchers understand the dynamics that occur within groups and how they interact with broader systems.