Exacta

A bet selecting the first and second horses in a race in the correct order. An exacta box refers to paying a little more to ensure they can finish in either order.

Minus Pool

A pari-mutuel pool – typically a show pool - where one horse is so heavily bet that after deductions there is not enough money left to cover the prescribed minimum on each bet.

Scratch

A horse is a scratch when injury or other necessity causes it to be withdrawn from the race.