The term 'Racetrack Postings' refers to the information posted at a racetrack that includes the names of the horses, jockeys, and trainers participating in a race, as well as the ODDS for each horse. The crossword solution for this term is 'ODDS', which are the numerical probabilities assigned to each horse in a race. These ODDS are determined by the bookmakers and are used to calculate the payouts for winning bets.