field horse (or mutuel field)
Two or more starters running as a single betting unit (entry), when there are more starters in a race than positions on the totalizator board.
filly
Breeding: Female horse four-years-old or younger.
Harness racing: A female horse 3 years of age or younger.
firm
A condition of a turf course corresponding to fast on a dirt track. A firm, resilient surface.
flag
Signal manually held at a short distance in front of the gate at the exact starting point of race. Official timing starts when flag is dropped by the “flagman” to denote proper start.
flatten out
A very tired horse that slows considerably, dropping its head on a straight line with its body. Some horses, however, like to run with their heads lowered.
floating
Flat plate or wooden implement (float) dragged over the surface of a wet track to aid in draining water.