Blinkers

A hood worn on a horse’s head to limit side vision, which can improve concentration. Blinkers are added or removed to relax a horse or give it more focus.

Underlay

A horse that is going off at lower odds than it deserves based on performance.

Pari-Mutuel

A pool style wagering system, where all money input through betting is divided among those with winning tickets (save for various deductions by the track operators).