The antonyms for breaking one word are joining, combining, merging, amalgamating, fusing, and unifying. Joining means to connect two or more separate pieces together. Combining is the process of putting together multiple items to create a single entity. Merging refers to blending two or more things into one. Amalgamating involves the mixing of different components to form a homogenous mixture. Fusing implies the bonding of two or more items into one. Unifying is the process of making things into a single unit or entity. These antonyms are useful in understanding how to construct words by either separating or combining them.