Collaterally can be replaced by variants such as indirectly, secondarily, or accompanying. While the word itself pertains to a secondary effect that occurs alongside the primary subject, its synonyms specifically emphasize the notion of linking a secondary idea to the foremost subject matter. Whether it be through an incidental impact or as a parallel occurrence that shadows the primary subject matter, collaterally encompasses more than just the direct effect. Some alternative synonym options that represent a cause-and-effect relationship include consequentially, consequent to, and as a result of. Collaterally, indirectly, or accompanying, the interchangeable nature of these words allows incisive communicative expression in a vast range of contexts.