Slimmish is a descriptive word that refers to something that is slightly or somewhat slim in nature. This term can be used to describe a wide range of things, from a person's physique to a piece of clothing. Some possible synonyms for slimmish include slender, lean, svelte, lithe, and trim. Each of these words carries a slightly different connotation, but all are suitable replacements for slimmish. For example, slender suggests a delicate and slender build, while lithe implies a graceful and agile physique. Ultimately, the choice of synonym will depend on the context and intended meaning of the sentence.