"Turn card" is a term commonly used in the game of poker to describe the fourth community card dealt face-up on the table. Antonyms for "turn card" would include "flop" and "river," which are the first and fifth community cards dealt in a game of poker, respectively. In other contexts, antonyms for "turn" may include words like "straight," "linear," or "unswerving," which describe qualities of movement or direction. Alternatively, antonyms for "card" might include words like "absence," "emptiness," or "void," which connote a lack of something rather than a tangible object.