tortuosity（n.） 英 [ˌtɔ:tjʊ'ɒsɪtɪ] 美 [ˌtɔtʃʊ'ɒsətɪ] early 15c., tortuosite, in medical use, "something twisted," from Old French tortuosite, from tortuos (see tortuous), and compare Medieval Latin tortuositas.该词起源时间：15世纪初
