Slimness is an adjective that describes someone or something as being thin or slender. There are many synonyms for slimness, such as thinness, skinniness, leanness, slenderness, and svelteness. Each of these words conveys the idea of being slim, but they can also have slightly different connotations. Thinness, for example, suggests a lack of substance or meat on the bones, while skinniness can have negative connotations of malnourishment. Leanness and slenderness have a more positive connotation, suggesting a healthy and athletic build. Svelteness is a more obscure term that suggests a graceful and elegant slimness.