For futher reference on their about page on their website

" So, after some thought the name The Great White Brotherhood was chosen. At the time it seemed the best name and described who this group were.

Great implied a large collection.
White implied purity of soul and ambition.
Brotherhood implied a group joining together with one aim.

However, over time, the meanings of words change.

Today, unfortunately:

Great implies noble.
White implies skin color.
Brotherhood implies a group exclusively male.

"