noun, noun which may take the genitive case particle 'no'
Political ideology advocating a republican form of government, where the head of state is not a monarch.
He strongly supports the ideals of republicanism.
共和主義的な改革が議論されている。
Republican reforms are being discussed.
共和主義 is the ideology or belief in republican governance, while 共和制 refers to the concrete political system in place.
Compound of 共和 (きょうわ, 'republic') + 主義 (しゅぎ, '-ism'). 共和 is a Meiji-era coinage from Chinese 共和, originally meaning 'joint harmony' and used to translate 'republic'.