Gandalf's cousin

[Eyalan]

Another question, I'm afraid

While Gandalf is introducing himself to Beorn, he mentions his cousin Radagast.
Obviously, Radagast wasn't really physically his cousin.
But perhaps Gandalf used the word 'cousin' as a term of affection?
Or maybe I'm reading too much into it, and it's just an inconsistency.
Once again, there may be no definite answer, but all opinions are welcome.

[Haldir]

Something like... "brother" perhaps? Like a sworn kind of thing...

[Arquenniel]

sworn cousin?

[Eyalan]

So you both think it's an emotional thing?

[Haldir]

Maybe. I know people who aren't actually birth brothers, but they are so close that they even call each other brothers and stuff.. and they become sworn brothers. I'm thinking that maybe Gandalf and Radagast are sort of like that?