The word "skinninesses" refers to the quality or state of being very thin. Some synonyms that can be used instead of skinninesses are thinness, emaciation, gauntness, lankiness, leanness, and svelteness. All of these words describe the physical characteristic of being underweight or having a slim build. It's important to note that using these words to describe someone can be perceived as negative or hurtful, so it's essential to use them with sensitivity and consideration. It's more appropriate to focus on a person's overall health instead of their physical appearance.