Definition & Meaning of "shit-eater"in English

What is the origin of the term "shit-eater" and how is it used?

"Shit-eater" is a slang insult that likely emerged in English in the 19th or early 20th century, combining "shit" (denoting filth, worthlessness, or moral degradation) with "eater" (someone who consumes or accepts) to create a vivid image of a person as disgusting, debased, or deserving contempt. The term relies on a grotesque metaphor to convey extreme disdain or moral judgment. It has appeared in informal speech, military slang, and literature to harshly criticize or insult someone's character or behavior. The word is clearly derogatory and offensive, rarely neutral, and intended to shock or demean.