Boogie with egghead at end of year assembly in a show of utter depravity (9)
I believe the answer is:
decadence
'depravity' is the definition.
(I've seen this before)
'boogie with egghead at end of year assembly in a show of utter' is the wordplay.
I cannot really see how this works, but
'egghead' could be 'e' (head letter of 'egg') and 'e' is found within the answer.
an anagram of 'end' is 'den' which is located in the answer.
'a' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for decadence that I've seen before include "Decline in quality" , "depravity" , "Progressive decline" , "Immoral behaviour" , "State of immorality and self-indulgence" .)