Addition is a word that is commonly used to describe the process of adding something to something else. However, there are many other words that can be used to describe this same process. Some synonyms for addition include augmentation, extension, inclusion, supplement, annexation, and attachment. These words all describe the act of adding something to something else, whether it be a physical object or a piece of information. Other synonyms for addition that are more specific include accretion, which describes the process of growth or increase, and conglomeration, which describes the combination of multiple things into one. Regardless of the word used, they all describe the process of adding something to something else.