Portmanteau of scrotum and runt. Must commonly used to describe the genitalia of a Tongan male after he's been in a freezer, although can be applied to their women and dogs as a deadly intertribal insult.
A noun meaning scrawny and runt-like. So a father decided to call his scrawny, little, runt-like Yorkie scrunt, which is a combination of both scrawny and runt.