The word "漏洞" is formed through a vivid conceptual metaphor. It literally combines the character for "leak" (漏) with the character for "hole" or "cavity" (洞), creating the mental image of a hole through which something escapes. This concrete picture of a flaw in a physical container (like a bucket with a hole that leaks water) is then applied abstractly to represent any kind of flaw, weakness, or gap in a system, plan, argument, or software, through which problems or failures can "leak" out.