The phrase "cashed in chips" refers to exchanging poker chips for cash or other prizes. The antonym, or opposite, of this phrase would be "betting with chips", where one would use their chips to make bets instead of exchanging them for cash. Other antonyms for "cashed in chips" could include "holding onto chips", where one decides to keep their chips and not use them for anything, or "losing chips", where one loses their chips due to unsuccessful betting or gameplay. These opposites highlight different strategies and outcomes in playing poker, and demonstrate the importance of making strategic decisions with one's chips.