The term 'balloon knot' is a descriptive piece of internet slang that colloquially refers to the appearance of the human anus. In meme culture, the phrase is most frequently used as a punchline to describe the physical aftermath of eating extremely spicy food or experiencing intense digestive distress. While the term existed in various subcultures for decades, it became a staple of digital humor on forums like Reddit and 4chan. It typically appears in 'That Face When' (TFW) scenarios or 'Me After' templates, where the creator wants to convey a visceral sense of discomfort or a 'tight' situation through crude, relatable anatomical humor.