What is the meaning of Tao? 

Tao or Dao is a Chinese word meaning ‘way’, ‘path’, ‘route’, or sometimes more loosely, ‘doctrine’ or ‘principle’. Within the context of traditional Chinese philosophy and religion, Tao is a metaphysical concept
In Taoism, Chinese Buddhism and Confucianism, the object of spiritual practice is to ‘become one with the tao’

The word “Tao” has a variety of meanings in both ancient and modern Chinese language. Aside from its purely prosaic use to mean road, channel, path, doctrine, or similar,[1] the word has acquired a variety of differing and often confusing metaphorical, philosophical and religious uses. In most belief systems, Dao is used symbolically in its sense of ‘way’ as the ‘right’ or ‘proper’ way of existence, or in the context of ongoing practices of attainment or of the full coming into being, or the state of enlightenment or spiritual perfection that is the outcome of such practices