Yes the answer by Philip is correct in this instance in regard to aircraft interiors, although in aircraft maintenance terminology, it usually refers to a pressure bulkhead, such as either side of the wheel wells, or at either end of the fuselage, such as between the cabin and the tail section.
Rainbow baby. A rainbow baby is a baby that is born following a miscarriage or still birth. In the real world, a beautiful and bright rainbow follows a storm and gives hope of things getting better. The rainbow is more appreciated having just experienced the storm in comparison. The storm (pregnancy loss) has already happened and nothing can change that experience. Storm-clouds might still be overhead as the family continue to cope with the loss, but something colourful and bright has emerged from the darkness and misery.
Random Rainbow Factoid: According to the 1973 U.S. Social Security Administration data, the first name Rainbow is not a popular baby girl's name in California. Imagine that, only 5 babies in California have the same name as you in 1973. Weird things about the name Rainbow: Your name in reverse order is Wobniar.