Riordan is an Anglicized form of the Gaelic name 'O' Rioghbhardain', where 'O' means 'son of' and the given name 'Rioghbhardan' is itself derived from the Gaelic words 'riogh', which means 'royal', and 'bhard', which means a 'bard or a poet'.
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Riordan is an Anglicized form of the Gaelic name 'O' Rioghbhardain', where 'O' means 'son of' and the given name 'Rioghbhardan' is itself derived from the Gaelic words 'riogh', which means 'royal', and 'bhard', which means a 'bard or a poet'.