Final answer:
The CF cephal/o refers to the head, as it is used in medical terms that relate to the head's structure and functions.
Step-by-step explanation:
The CF (combining form) cephal/o refers to the head. In medical terminology, it is often used as a prefix in various terms related to the head or the anatomy of the head. For instance, cephalochordata and cephalothorax both include the root cephal/o, indicating the portion related to the head. Other related terms include cerebral cortex, which is the outer layer of the cerebrum, and cranial nerve, which is one of twelve nerves directly connected to the brain, responsible for sensory or motor function in the head and neck area.