Endosome is a cellular organelle involved in the sorting, processing, and trafficking of proteins. It is an essential component of the endocytic pathway, which is responsible for the internalization of extracellular molecules into the cell. In addition to the term endosome, there are several synonyms for this organelle, such as early sorting endosome, late endosome, recycling endosome, and trans-Golgi network. These different endosome subtypes are distinguished by their localization, morphology, and function. Furthermore, depending on the cell type and biological context, endosomes can be referred to by different names, such as endocytic vesicles, endocytic vacuoles, or endocytic compartments. Overall, understanding the different synonyms for endosomes is crucial for comprehending the complex mechanisms of protein trafficking and cellular homeostasis.