Running mouse
A mouse darting across the floor — a small fast thing moving along the edge of the room you almost did not see.
A running mouse in a dream is the dream's image of a small fast thing moving along the edge of the room you almost did not see. The mouse does not announce; the mouse is registered in the corner of the eye and is gone before the rest of the room has caught up. The dream brings the running mouse when something in your life — a small fear, a darted thought, a piece of information that crossed your attention and was not quite caught — has moved through and is now somewhere under the furniture. A mouse seen and named is the dream affirming that the small fast presence was noticed. A mouse known to be in the house but never seen again is the dream noting that the small darting thing is still inside the walls and is no longer locatable.