From Old Galician-Portuguese queixada (“jaw”), from Vulgar Latin *capseāta, a derivative of Vulgar Latin *capseus (“chin”) (whence queixo), itself a derivative of Latin capsa (“box”), from capiō (“capture, seize, take”), from Proto-Indo-European *keh₂p- (“to take, seize, catch, grasp”). By surface analysis, queixo + -ada.