The Bawwi are mentioned by Wendelle Stevens when he is talking about giant races that visited Earth. The name refers to the name of the race. Their place of origin is unknown, or at least, not specified in the documentation. What we do know is that they belong to the ethnical group of the Lyran Giants. They are said to be 2.5 to 3 meter tall and would have visited Earth in Atlantean and Lemurian times.

Note the similarity, however, to the word 'Baavi,' - sometimes even spelled Baawi, - which allegedly is the name of a planet circling Proxima Centauri.
These, however, are said to be standard human size, not 'Giants.