dumpster cunt

There is no direct translation for "dumpster cunt" in Sindarin, as it is a modern English vulgarity and Sindarin is a fictional Elvish language from J.R.R. Tolkien's Middle-earth, which does not include modern or vulgar expressions. However, an equivalent expression capturing the intended insult might be: "gwaur gûr," which translates to "filthy heart.