There is an Indian word: Maha
It means great, or ultimate.
If one translates it into Chinese then one
would not be mistaken to employ the term Taiji.
Maha is supreme, it is ultimate.

The Maha mantra is the ultimate mantra.
The Maharishi is the ultimate rishi.

The bagua is 8 fold.
The dharma is 8 fold.
Laozi left China and went to India.
There it is said by some that he taught a young prince.
The teachings involved can be found in the Hua Hu Ching.