The most common and most likely answer to this crossword clue is the 4 letter word COIN
I've seen this crossword clue in The Guardian
C
O
I
N
More clues leading to the result COIN
- Change from upright character into criminal
- Bit of money I invested in fiddle
- Swindle involving current 50p, say
- Company not out to make money
- Firm concerned with making money
- Cousin leaving us a small amount of money
- Bob, say, dislodges top of gargoyle from keystone
- Anna possibly stealing Colin’s heart
- Cousin must ignore American strike
- Stamp name for Penny
Buddy explains!

The straight part
We know that "money" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case money = coin.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 COIN mean?
COIN noun- (money) A piece of currency, usually metallic and in the shape of a disc, but sometimes polygonal, or with a hole in the middle.
- A token used in a special establishment like a casino.
- That which serves for payment or recompense.
- Money in general, not limited to coins.
- One of the suits of minor arcana in tarot, or a card of that suit.
- A corner or external angle.
- A small circular slice of food.
- A cryptocurrency.
- To make of a definite fineness, and convert into coins, as a mass of metal.
- (by extension) To make or fabricate.
- To acquire rapidly, as money; to make.