Muddled; rotten (6)
I believe the answer is:
addled
I believe this is a double definition.
'muddled' is the first definition.
(synonyms)
'rotten' is the second definition.
(I've seen this before)
(Other definitions for addled that I've seen before include "Confused and vague" , "Perplexed -- rotten" , "became rotten" , "(Of an egg) went bad" , "Of egg, rotten and producing no chick" .)