The difference between the words starving and hungry is an example of?

positive connotations denotative meaning

shades of meaning negative tone

This would be the shades of meaning. While both may have the same (or similar) denotative meaning, the shades of meaning show that one is a much stronger concept than the other. The first word brings to mind a much harsher need for food than simply being "hungry," which is a bland, generic term by comparison.