Country Uranus cut off (5)
I believe the answer is:
nauru
'country' is the definition.
(I know that Nauru is a country)
'uranus cut off' is the wordplay.
'cut' means to remove the last letter.
'off' is an anagram indicator.
'uranus' with its last letter taken off is 'uranu'.
'uranu' anagrammed gives 'NAURU'.
(Other definitions for nauru that I've seen before include "Pacific republic, formerly Pleasant Island" , "Pacific island country" , "SW Pacific republic" , "Small Pacific republic" , "Smallest Pacific state" .)