Cephalalgia comes from Late Latin cephalalgia, from Greek kephalalgia ('headache'), from kephale ('head') + algos ('pain'). The historical trail runs through kephale in Ancient Greek and algos in Ancient Greek. Morphologically, cephalalgia is transparent: it draws on Late Latin cephalalgia, from Greek kephalalgia ('headache'), from kephale ('head') + algos ('pain'). Used as a noun, cephalalgia now means "headache, especially as a medical symptom", so the present definition can be read against the older forms and meanings. The same lexical family is also visible in related forms such as cephalic and encephalitis. The result is a borrowed or transmitted form whose modern spelling carries a compact record of its route into English.