Sinkhole
Ground that has opened under itself — a familiar surface suddenly revealing it was hollow underneath.
A sinkhole in a dream is the dream's image of a familiar surface revealing it was hollow underneath. Sinkholes do not happen on weak ground; they happen on ground that looked solid until a process beneath it finished. The dream brings the sinkhole when something in your life — a trust, a financial arrangement, a piece of certainty — has just dropped through, and what is now visible was happening invisibly for a long time. A sinkhole noticed at a safe distance is the dream telling you the warning was received. A sinkhole that has taken something with it as it opened is the dream marking a loss that has already happened and is not recoverable.