1. To stop and begin moving in the opposite direction. Said especially of athletes on the field during gameplay. The quarterback tried reversing his field to evade the defensive linesmen, but he wasn't quick enough and ended up getting sacked in the end zone. As soon as we saw the family of bears, we quietly and hastily reversed field.

2. To suddenly hold or profess a position or opinion that runs contrary or opposite to one held previously. The senator seemed to reverse field the following day, stating that he would never condone police violence against any citizen. The city's legal team spent months convincing the judge to reverse her field and allow the case to proceed.