What are the opposite words for thinness?

Thinness refers to a state of being slender or physically slim, but there are numerous antonyms (words with opposite meanings) that can be used to describe the opposite of thinness. Some common antonyms for thinness include thickness, plumpness, robustness, fullness, roundness, and heftiness. These words are often used to describe a more substantial body type or physique, and can be used in a variety of contexts where thinness is not desirable or appropriate. For instance, a person may strive to gain weight and build muscle for health reasons, or to achieve a more aesthetically pleasing appearance. In any case, antonyms for thinness provide a useful contrast to this popular descriptor of body size and shape.