The term "in firmer" does not exist in the English language. However, if we were to consider the opposite of "firmer," it would be "softer." Softer objects have a lower density and are more pliable, with less resistance to pressure. Some antonyms of "firmer" that could be used in different contexts include "looser," "weaker," "more flexible," "less rigid," or "less taut." It is essential to have a broad understanding of antonyms because they can help in the context of communication and expressing different ideas. By using antonyms, we can express the exact opposite meaning of a given word to convey a more precise message.