FOMO is shorthand for fear of missing out, a phrase widely used online for the anxiety of being excluded from an event, release or trend. This short clip has circulated as a reaction sound rather than a known scene from a film or show, so its use is tied to memes and edits instead of a specific character. Creators add it when a character or friend discovers news too late, turning simple disappointment into exaggerated panic that other viewers recognise from group chats, gaming lobbies and social feeds.