Strong interrelation refers to a connection or correlation between two or more variables, factors or entities that have a significant impact on each other's performance or behavior. Some synonyms for strong interrelation include strong correlation, close association, tight connection, firm tie, robust linkage, powerful nexus, sturdy bond, and reliable interconnection. These words are often used interchangeably based on the context of the situation and the intended meaning of the sentence. However, the use of each synonym could vary depending on the situation, subject matter, or context of the statement. Overall, having a solid understanding of these synonyms can greatly enhance one's communication skills and ability to articulate complex ideas.