Rabbit

Also known as a pacemaker; this is a horse with no expected chance of winning but is used to prompt a quick pace on the front end of the race to the benefit of a stablemate who is a closer.

Dead Heat

Two or more horses finishing so close at the wire, that they were unable to be separated on a photo finish and deemed to have tied.

Stewards

The officials watching every race at a meet to enforce the rules.