Definition of "jumpout" []

• A separation from a groove, track, etc., that otherwise constrains motion. (adjective)
• An unofficial trial race. (adjective)
• A plainclothes narcotics officer. (adjective)

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• "Black Caviar clears away from her jumpout field in customary fashion."
• "So You Think disappointed in a barrier jumpout at Flemington yesterday."
• "He is currently third favourite for the Australian Guineas (1600m) behind Denman and So You Think, who will have a jumpout on Friday before resuming in the Autumn Stakes on February"