this, (definition section 2, number 3), it can mean $500.
Could "a nickel" mean 5000 in the following dialogue?
It seems that it doesn't make sense otherwise.
"$15,000. $16,500 with the vig. Turns out this guy's been calling in
bets under three different names. Always calling around 6:00, 7:00
in the morning when he's sure that the runners were covering the
phones. He bet a nickel three times on the Grizzlies giving 3 1/2.
Didn't have the sense to pay for a half point. Not that it would
have made a difference."
And "vig" is presumably some kind of betting tax - try Google.
Yes, it's short for "vigorish." It's what mobsters use refer to the interest or fee they charge for their services.
In the US, the five cent piece is called a "nickel." The term has since become colloquial usage for any phrase that involves the numeral five. For example, on the TV show M*A*S*H quite often someone referring to the 8055 unit would articulate it as the "eight oh double nickel."