Sheesh has long been slang for surprise or disbelief, but it exploded online as a TikTok trend in 2021, when creators began using the drawn-out pronunciation to react to impressive reveals, transformations and flexes. The sound spread through reaction videos, edits and duets, becoming a shorthand way to say something was unexpectedly cool without explaining it. Its icy, exaggerated delivery made it easy to recognise and reuse, and it remains popular in short-form edits where a quick burst of hype says more than a caption.