Hello! I was wondering are you allowed to use "Facebook" in a domain? i contacted facebook a few weeks ago asking them this via email but still no reply
As long as you aren't buying the domain and saying to Facebook "hey i got this domain, wana buy it from me?" Also, you should include somewhere on the page "This website is in no way affiliated with Facebook, Inc. (facebook.com)"
If you don't make money off their trademark, maybe. And if you do, be aware that no disclaimer is necessarily going to shield you from them.
It is their trademark and having a domain with facebook in it, can be risky. If they find you out earning money using their tradermark, they will surely take some action. but most probably, there wont be a problem.
And not make money off their trademark as stated earlier, although the OP had stated the intent: Unfortunately you can't without Facebook's explicit permission. They might or might not take action against you if you proceed, but that's solely for them to decide despite what everyone else thinks.