The rotten toady finishes tonight! (5)
I believe the answer is:
today
'finishes tonight' is the definition.
'today' can be an answer for 'tonight' (thesaurus). I'm unsure of the 'finishes' bit.
'the rotten toady' is the wordplay.
'the rotten' indicates an anagram.
'toady' anagrammed gives 'TODAY'.
Can you help me to learn more?
(Other definitions for today that I've seen before include "At the present time, in general" , "one of our papers, once" , "Modern times" , "The present time or age" , "Nowadays" .)