Reconsidered Arctic riot as noble (12)
I believe the answer is:
aristocratic
'noble' is the definition.
(similar in meaning)
'reconsidered arctic riot as' is the wordplay.
'reconsidered' indicates an anagram.
'arctic'+'riot'+'as'='arcticriotas'
'arcticriotas' with letters rearranged gives 'ARISTOCRATIC'.
(Other definitions for aristocratic that I've seen before include "Of noble birth" , "classy" , "Patrician" , "Upper-class" , "Of the nobility" .)