Liquid Nightmare Share definition Flag 1: An excessively violent sexual dream or fantasy. Often very unpleasant. 2: An up and coming DJ "Man, had a liquid nightmare last night, I dreamt I got mounted by a horse and pummelled until my anus bled." Liquid Nightmare by Bon-Bon9312 December 6, 2011 0 0 Get merch Get the Liquid Nightmare mug. Buy Now — $32.95 See more merch