Dome of Silence
From Equestripedia, the Archives of Equestria!
The Dome of Silence was a spell used by Twilight Sparkle.
Applications
The Dome of Silence does what its name implies, creates a spherical dome of soundproof walls, allowing for its speakers inside the dome to converse without being heard. Twilight used this spell while in the Canterlot Library to communicate with Moon Dancer without annoying the other people in the library.
