Authoritarian Adriatic lot thrown out (11)
I believe the answer is:
dictatorial
'authoritarian' is the definition.
(I know that authoritarian can be written as dictatorial)
'adriatic lot thrown out' is the wordplay.
'thrown out' indicates an anagram.
'adriatic'+'lot'='adriaticlot'
'adriaticlot' anagrammed gives 'DICTATORIAL'.
(Other definitions for dictatorial that I've seen before include "tyrannical" , "Autocratic" , "Given to telling others what to do" , "Overbearing" .)