Left Wales out, small and anarchic (7)
I believe the answer is:
lawless
'anarchic' is the definition.
(I know that anarchic can be written as lawless)
'left wales out small' is the wordplay.
'left' becomes 'l' (common abbreviation).
'out' indicates an anagram (out can mean wrong or inaccurate).
'small' becomes 's' (abbreviation - e.g. clothes size).
'wales' anagrammed gives 'awles'.
'l'+'awles'+'s'='LAWLESS'
'and' acts as a link.
(Other definitions for lawless that I've seen before include "Unruly - anarchic" , "disobedient" , "Anarchic, without any controls" , "Ungoverned" , "Anarchy" .)