The word "那厮" is formed by combining the demonstrative "那" (meaning "that") with "厮", a character originally denoting a male servant or menial laborer that later evolved into a derogatory term for a person, akin to "fellow" or "guy". When merged, they create a compound noun phrase literally meaning "that fellow", used pejoratively to refer to a distant or despised individual, primarily in historical or literary Chinese contexts.