The most common and most likely answer to this crossword clue is the 5 letter word JOKER
I've seen this crossword clue in The Times
J
O
K
E
R
More clues leading to the result JOKER
- Yank almost to the end in possession of fine wit
- Card game wherein jack trumps first card
- GIpalms king and another card
- John Kerry loses footing twice getting to one of 19
- Card acceptable in one half of Jersey
- Card  trickster
- Villain in a pack
- Juliet’s alright about returning wild card
- Brand centre-half a showman
- Wag, one appearing in pack?
Buddy explains!
The straight part
We know that "wit" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case wit = joker.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does JOKER mean?
JOKER noun- A person who makes jokes.
- A funny person.
- A jester.
- A playing card that features a picture of a joker (that is, a jester) and that may be used as a wild card in some card games.
- An unspecified, vaguely disreputable person.
- A man.
- A clause in a contract that undermines its apparent provisions.