Casino worker's cough getting worse? (8)
I believe the answer is:
croupier
I believe this clue is a double definition.
'casino worker's' is the first definition.
(worker in charge of a gambling table)
'cough getting worse?' is the second definition.
(as in croup, coughing disease in infants)
(Other definitions for croupier that I've seen before include "Worker raking it in at the casino!" , "Casino employee" , "I procure from person in charge of gambling table" , "Leisure worker" , "Roulette attendant" .)