Not even arranged right! (5)
I believe the answer is:
never
'not' is the definition.
(thesaurus)
'even arranged right' is the wordplay.
'arranged' is an anagram indicator.
'right' becomes 'r' (common abbreviation).
'even' with letters rearranged gives 'neve'.
'neve'+'r'='NEVER'
(Other definitions for never that I've seen before include "At no time in the past or future" , "I refuse" , "'It's now or - - ' (14 song)" , "Do not give up!" , "Strong negative" .)