migraine: [14] The earliest English forms of this word were mygrame and mygrane, but eventually it became institutionalized as megrim. Not until the 18th century did what is now the standard form, migraine, begin to appear on the scene, probably as a reborrowing of the word’s original source, French migraine. This came via late Latin hēmicrānia from Greek hēmikrāníā, literally ‘half-skull’ (krāníon is the source of English cranium [16], and is distantly related to English horn). The etymological idea underlying the word is of ‘pain in one side of the head’. => cranium, horn
