Appearance of an unwanted character in party politics (4)
I believe the answer is:
typo
'appearance of an unwanted character' is the definition.
'typo' can be an answer for 'character' (I have seen 'False character' mean 'typo' so perhaps 'character' could also mean 'typo'). I am not certain of the 'appearance of an unwanted' bit.
'in party politics' is the wordplay.
'in' says the answer is hidden in the clue.
'TYPO' can be found hidden inside 'party politics'.
Can you help me to learn more?
(Other definitions for typo that I've seen before include "Mistake in printed matter, in short" , "Small printing error" , "Printer's mistake" , "Thanks; good health!" , "False character" .)