The BuddyPress domain policy mirrors that of the WordPress domain policy.
We ask if you’re going to start a site about BuddyPress or related to it that you not use “BuddyPress” in the domain name. Try using “bp” instead, or another variation.
If you already have a domain with “BuddyPress” in it, redirecting it to the “bp” equivalent is fine, just as long as the main one users see and you promote doesn’t contain “BuddyPress.”
“BuddyPress” in sub-domains is fine, like buddypress.example.com, we’re just concerned about top-level domains.