Devious US uni so in need of reform (7)
I believe the answer is:
sinuous
'devious' is the definition.
(thesaurus)
'us uni so in need of reform' is the wordplay.
'uni' becomes 'u' (U is an abbreviation for university).
'need of reform' indicates anagramming the letters (I've seen 'needing reform' mean this).
'us'+'u'+'so'+'in'='ususoin'
'ususoin' anagrammed gives 'SINUOUS'.
(Other definitions for sinuous that I've seen before include "Snakelike" , "Supply bending; wavy" , "Full of curves, bends" , "Having many curves and turns" , "Twisting and turning" .)