Singing aloud
Letting the voice out at full volume — expression released past the censor.
Singing aloud in a dream is the dream's image of expression released past the internal censor. Singing is voice committed to the room; you cannot quietly take it back. The dream brings the action when something in you — a feeling, an opinion, a piece of joy — has been ready to come out and is finally coming out. Singing well in front of others is the dream telling you the expression was received and the exposure was worth it. Singing that cuts off mid-note, or that comes out wrong, is the dream noting that the censor reasserted itself at the moment of release.