Pap/pæp/ Definition 1 of 4Pro Tip 1/2Infant Feeding Pap refers to food for babies, typically very soft and easy to digest. As a newborn, the infant will mostly consume pap for nourishment. Pro Tip 2/2Careful Use When used for adults, 'pap' implies the food is overly simple or unrefined. The grown man grumbled about being fed pap after his dental surgery.