This is both complicated and easy. The easy bit is that "praxis" is the German word for practice; a physician might have a private practice, and in German that's "praxis." So yeah, it can be a way to showcase one's book larnin' if one is prone to trying to impress others with a sprinkling of foreign loan words into one's conversations. Like when people refer to that never-finished book by Marx, "Das Kapital" as if they were reading it in German...
Having said that, it's also a possibility that someone is using it the way I first learned it in my early college years: the integration of theory with practice, a lived synthesis, a learning experience that refines one's theories as they are acted out in the real world. I remember that as the sense of its use in both political science and philosophy classes. However, it could just be the fancy (and ultimately empty) wordplay of Anglophone Hegelian wankers, who think of theory and practice as a polarized binary.
The general guideline for using loan words is that if there's a larger and wider sense (or some ambiguity) in the original language, you can use it instead of a simple translation. "Praxis" doesn't really fit those criteria because it really just means practice. Unless one wants to say why one is choosing to inflate the meaning in the sense of the preceding paragraph, in which case it might be okay.
