Causa causans is a Latin phrase that means an underlying cause or a primary cause. It is a term that is used in various fields such as philosophy, psychology, and medicine. There are several synonyms that can be used for causa causans, including root cause, underlying factor, fundamental reason, and core issue. These synonyms can help to add depth and clarity to discussions around the causes of various phenomena and events. By exploring the various synonyms for causa causans, one can gain a deeper understanding of the complex causal relationships that underlie many phenomena and events in both the natural and social worlds.