There are many antonyms for the word "chillers," which refers to things that are cool or cold. Some possible antonyms include "heaters," "warmers," "hot plates," "burners," "stoves," "furnaces," and "ovens." These words all describe things that generate heat, either to cook food or to warm up a space. They are the opposite of "chillers," which work to keep things cold or cool. Other antonyms for "chillers" might include "sweaters," "coats," "insulation," or "blankets," which all help to keep a person or object warm despite cold temperatures outside.