Autocrator is a less common term used to describe someone who possesses absolute power or authority. However, there are several synonyms for this word that are more commonly used in everyday language. One synonymous term is "dictator", which refers to an individual who exercises complete control and decision-making in a nation. Another synonym is "tyrant", which carries the connotation of a ruler who governs with oppressive or cruel methods. Additionally, "despot" is a term often used to describe an autocratic leader who wields unlimited power and often rules with an iron fist. These synonyms all convey the idea of a ruler with unchecked authority and dominance over others.