Concatenation event refers to the merging of two or more things in a sequence. There are various words that can be used as synonyms for this term. One of the popular words that can be used as a synonym for concatenation event is "fusion". Other synonyms for this term include "meld", "blend", "union", "amalgamation", "integration", "linkage", "collation", "junction", "connection" and "combination". These words essentially express the same idea of things coming together to form a whole. Each of these synonyms can be used interchangeably with the term concatenation event, depending on the context and preference of the writer or speaker.