Antonyms are words that have opposite meanings to another word. For the term "turning corner," which typically signifies progress, there are several antonyms. One antonym could be "stagnating," which means to remain motionless and not progress. Another antonym could be "regressing," which means to go back to a previous state or position. Additionally, "backtracking" could be an antonym for turning a corner, signifying moving in the opposite direction. Finally, "failure" could be an all-encompassing antonym, indicating that progress has not been made, and a goal has not been achieved. Overall, antonyms can provide us with an array of language to express contrasts and alternative perspectives.