The term 'lying down' can be described in two ways: PRONE and RECUMBENT. PRONE is a five-letter word meaning to lie face down, while RECUMBENT is a nine-letter word meaning to lie down in a reclining position. Both words refer to the act of lying down, but they differ in the position of the body. PRONE implies that the person is lying flat on their stomach, while RECUMBENT implies that the person is lying in a more relaxed position, such as on their back or side.