A synonym of “usurp” is “seize”.
“Usurp” means to take power or a position unlawfully or by force. For example, “He tried to usurp the throne by staging a coup.” It implies an improper or unethical takeover.
“Seize” can also mean to take possession of something forcefully or suddenly. For instance, “The rebels seized the palace and took control of the government.” While “seize” can be used in a broader context than just taking power, it shares the sense of taking something without proper authority.
Another synonym could be “appropriate”. This word suggests taking something for one’s own use, often without rightful claim. For example, “He appropriated the company’s funds for his personal expenses.” In the context of power or position, it can mean taking something that doesn’t belong to you.
In summary, “usurp”, “seize”, and “appropriate” all convey the idea of taking something without proper authorization, especially when it comes to power or possession.