Sheesh started as slang for impressed disbelief and exploded as a TikTok reaction in the early 2020s, where creators paired the stretched pronunciation with the ice-in-my-veins gesture and clips of impressive looks, skills and reveals. The sound travelled far beyond its first viral videos because it needs no explanation: the longer the vowel, the stronger the approval. It remains a staple reaction in short-form edits, memes and streams, used to mark a moment as cool without interrupting the visual joke.