Panic, miss beginning and slip (5)
I believe the answer is:
error
'panic miss' is the definition.
'error' can be an answer for 'miss' (thesaurus). I'm unsure of the 'panic' bit.
'beginning and slip' is the wordplay.
'beginning' becomes 'or' (I am not sure about this - if you are sure you should believe this answer much more).
'and' is a charade indicator (letters next to each other).
'slip' becomes 'err' (to err is to make an error).
'or' after 'err' is 'ERROR'.
Can you help me to learn more?
(Other definitions for error that I've seen before include "Fallacy, mistake" , "Mistake or fault" , "Boo-boo" , "Mistake or mishap" , "Mistake, lapse" .)