republican
adjective
[ rɪˈpʌblɪk(ə)n ]
• (of a form of government, constitution, etc.) belonging to or characteristic of a republic.
• "they reiterated their demand of abolition of the monarchy and creation of a republican state"
• (in the US) supporting the Republican Party.
republican
noun
• an advocate of republican government.
• "those who favored the continuance of the republic made every effort to defeat the monarchists and to have republicans elected in their places"
• (in the US) a member or supporter of the Republican Party.
• an advocate of a united Ireland.