The Dao is the more recent translation of the word formerly rendered Tao. The original Chinese term, in ordinary usage, means the Way. However, in Daoism (Taoism), it became a philosophical concept of great depth, pervasive to the philosophy, and one of its teaching is that
The Dao which can be explained is not the true Dao.
Therefore, the Dao "exists in wordlessness" -- it exists though it can not be explained in words -- and because it is the fundamental root of things, it is complete in itself, always beginning and ending things properly. More or less.
This will get deep into philosophy if you want to consider it further.