Comment by jakeogh

"based" in that context, like "my friend is pretty based" is slang. Very common in circles that are happy about the election outcome and the current US economy etc. Admittedly it's recent (2016ish) slang in that usage. It's basically like like saying "my friend is well grounded" or more specifically "my friend has self consistent opinions" with a touch of "I agree with my friends opinions". Please don't ask me for a cite, it's too new, and I would rather not link to a hundred thousand reddit posts.