What is the origin of the idiom "other half" and when to use it?

The origin of the idiom "other half" can be traced back to ancient Greek philosopher Plato's dialogue called "The Symposium." In this dialogue, Plato describes the concept of soulmates, stating that humans were originally complete beings but were split in half by the gods. The idea of finding one's "other half" to feel complete and whole resonated through various cultures and influenced the modern usage of the term. The idiom "other half" refers to a person with whom one is married or in a romantic relationship. It signifies a deep emotional connection and often implies that the person is considered to be a perfect match or a significant part of one's life.