If you've heard the term "minyan," it means a prayer quorum of ten Jews/Jewish men.

Thanks for the link. I think that praying/being religious ostentatiously hasn't been as much of an issue for Judaism during most of its recent history, because Jews were more likely to be persecuted than praised for doing that. The Jews that I hang out with are mostly not very observant, so I can't tell you about how that issue is dealt with nowadays. The being pious in public vs. in private issue reminds me of Maimonides and his eight degrees of charity, though.