The clip is best understood as a short reaction sound rather than a line from a known show or film, and its exact original recording is not clearly documented. Online it circulates as a standalone vocal effect, shared and reused because the long, open syllable is easy to recognise and easy to drop over almost any visual. Creators use it as shorthand for shock, disbelief or comic exaggeration, especially in short-form videos where a single sound has to do the work of a full reaction. Its simplicity is why it keeps getting reused.