Opposed to or against monarchy, monarchical rule, or monarchical power.
From anti- + monarchic (from monarchy + -ic, an adjectival suffix). This variant emphasizes opposition to the practice and exercise of monarchical rule.
What's fascinating is that some antimonarchic societies (like Britain today) kept the monarch but stripped away the actual power—so they're antimonarchic without being antimonarchists, which is a brilliant compromise historically speaking.
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