The most common and most likely answer to this crossword clue is the 5 letter word MULCT
M
U
L
C
T
More clues leading to the result MULCT
Buddy explains!

The straight part
We know that "fine" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fine = mulct.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 MULCT mean?
MULCT noun- A fine or penalty, especially a pecuniary one.
- To impose such a fine or penalty.
- To swindle (someone) out of money.