A term used to describe betting market investment from punters who are well informed.
This can include professional punters or even owners who have knowledge about a horse, not known to the wider public.
Smart money if often seen in early betting markets, when bookmakers have recently set their prices for upcoming horse races.
Bookmakers often react by shortening their odds on the horse which has received investment which is considered smart.
"Get on that thing, it's come into $2.20 in the last hour and you can be sure there's smart money all over it."