Workers in this stable ruined business (13)
I believe the answer is:
establishment
'business' is the definition.
(I've seen this before)
'workers in this stable ruined' is the wordplay.
'workers' becomes 'men' (man is a kind of worker).
'in' indicates putting letters inside.
'ruined' indicates an anagram.
'this'+'stable'='thisstable'
'thisstable' anagrammed gives 'establisht'.
'men' put within 'establisht' is 'ESTABLISHMENT'.
(Other definitions for establishment that I've seen before include "Those in power" , "system" , "Permanent staff; business; household" , "concern" , "Power-wielding class" .)