: a person who believes in or supports a republican form of government. 3. Republican: a person from Northern Ireland who believes that Northern Ireland should be part of the Republic of Ireland rather than the United Kingdom — opposite loyalist.republican /rɪˈpʌblɪkən/ adjective.+] more examples [-] hide examples [+] Example sentences [-] Hide examples. 2. : relating to or based on a form of government in which representatives are elected and there is no king or queen. republican reforms. a republican government. [+] more examples [-] hide examples [+] Example sentences [-] Hide examples.