PICU Share definition Flag A pediatric intensive care unit is an area within a hospital specializing in the care of critically ill infants, children, and teenagers. My neighbour's daughter is in the PICU after being invloved in a very severe automobile accident. PICU by Eduardo1271 August 14, 2012 0 0 Get merch Get the PICU mug. Buy Now — $32.95 See more merch