? = Wordplay.
(!n) = The nth character of the clue isn't actually in the final word, and should be replaced with something else.
(V) = Remove all vowels (AEIOU); e.g. "hello" → "hll".
(C) = Remove all consonants; e.g. "hello" → "eo".
(<>) = Reverse the clue.
(-n) = Remove n letters from the end of the clue.
(n-) = Remove n letters from the start of the clue.