Etwas öffnen
Etwas herauslassen oder sich in etwas hineinlassen — eine bewusste Bewegung.
Opening something in a dream — a door, a box, a letter — is the dictionary's image of a deliberate move into or out of a contained state. The thing being opened is usually the symbol; the act of opening is the dream confirming that you have chosen to engage.
Where you often see it. Opening a door to a room you forgot. Opening a letter you did not expect. The dream uses opening for letting something out or letting yourself into something — a deliberate move.
What it is not. Opening is not always welcome. The dictionary reads it as the act of committed access.
Related in the dictionary. Read opening with door, letter, closing (its counterpart), and any scene of new access.