The term "royal hierarchy" can be replaced by other similar words such as "monarchial structure" or "regal system". Alternatively, one could use "courtly order" or "nobility ranking" to describe the ranking system within a royal family or court. "Kingly hierarchy" or "aristocratic hierarchy" may also be used to convey the same idea. Additionally, words such as "imperial ladder" or "sovereign hierarchy" could be utilized to describe the hierarchy within an imperial court or government. Overall, there are various synonyms for "royal hierarchy" that can convey the idea of a structured system of authority within a royal court or family.