".Heterosemy can be seen as a special case of polysemy, with the difference that in polysemy, the related meanings of a form is associated with the same lexeme.For example, the word "hard" has the related meanings "solid" (as in "a hard surface") and "difficult" (as in "a hard question"), but since the word is used as an adjective in both cases, it is straightforwardly classified as an instance of polysemy.