"DNF" stands for "Did Not Finish," a term commonly used in competitive sports, particularly in events like marathons, triathlons, and cycling races. It indicates that a participant started the event but was unable to complete it for various reasons, such as injury, fatigue, or time constraints. In official race results, a DNF is recorded to signify that the athlete did not finish the course. This designation helps maintain accurate records and statistics for events, allowing organizers and participants to understand performance levels and challenges faced during the competition.