Kowtow, which is borrowed from kau tau in Cantonese (koutou in Mandarin Chinese), is the act of deep respect shown by prostration, that is, kneeling and bowing so low as to have one's head touching the ground. An alternative Chinese term is ketou; however, the meaning is somewhat altered: kou (叩) has the general meaning of knock, whereas ke (磕) has the general meaning of "touch upon (a surface)", tou (頭) meaning head. The date of this custom's origin is probably sometime between the Spring and Autumn Period, or the Warring States Period of China's history because it is already known to have been a custom by the time of the Qin Dynasty (221 BCE - 206 BCE).
In East Asian culture, the kowtow is the highest sign of reverence. It was widely used to show reverence for one's elders, superiors, and especially the Emperor, as well as for religious and cultural objects of worship. In modern times, usage of the kowtow has become reduced....LESS