Corruption (3)
'corruption' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for decadence that I've seen before include "Perishing state" , "Progressive decline" , "Immoral behaviour" , "Decline in quality" , "Degeneration" .)
'corruption' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for evil that I've seen before include "Profoundly malevolent" , "Satanic" , "Harmful; unlucky" , "Malign" , "'The ... that men do lives after them' (Shakespeare)" .)
'corruption' is the definition.
(rot can mean corruption or decay)
This is the entire clue.
(Other definitions for rot that I've seen before include "Decomposition" , "Decay - nonsense" , "SECOND PART OF 25" , "Deterioration" , "Decay in grotesque way" .)