The word "惊厥" is formed by combining the character "惊", a phono-semantic compound where "忄" (heart/mind) conveys the semantic domain of emotion and "京" provides phonetic approximation, meaning "to frighten", with the character "厥", also a phono-semantic compound where "疒" (sickness) conveys illness and the component "欮" offers phonetic cues, meaning "fainting" or "convulsing"; together they logically describe a medical condition of convulsions typically induced by fright.