Rowdy underworld boss gets hospital attendant (10)
I believe the answer is:
disorderly
'rowdy' is the definition.
('disorderly' can be similar in meaning to 'rowdy')
'underworld boss gets hospital attendant' is the wordplay.
'underworld boss' becomes 'dis' (I am not sure about this - if you are sure you should believe this answer much more).
'gets' is a charade indicator (letters next to each other).
'hospital attendant' becomes 'orderly' ('orderly' can be a synonym of 'hospital attendant').
'dis'+'orderly'='DISORDERLY'
(Other definitions for disorderly that I've seen before include "Unruly" , "Lacking organisation" , "a mess" , "Companion of drunk" , "confused?" .)