The phrase erm what the sigma grew out of TikTok slang, where sigma became shorthand for a cool, independent character and the full line was used as a mock-serious reaction to something strange or cringeworthy. It spread through short-form reaction videos, gaming clips and comment sections, often delivered in a flat, deadpan voice. Bass-boosted and distorted remixes followed, exaggerating the joke for louder edits, and the sound remains popular because its confused tone works as an instant punchline for almost any awkward moment.