Idiom of the day - Vanish into thin air Meaning: To disappear completely. Example: Have you seen my phone? It's vanished into thin air. If you'd like to practice using this idiom, please write back to me on this post with an example and I'll tell you if you're using it correctly :D Finally, if you're looking for a friendly and patient teacher please check out my profile. I look forward to meeting you. Thank you, Rianne :)