Personally, when someone says Genius, in some contexts, I take it like an excuse to justify the existence of people that excel doing something, just because they are born-geniuses.
The fact that some of these geniuses dedicated their entire lives to improve themselves (being it by practicing on an instrument or doing math, for example) is left aside, and the justification for doing practically nothing to achieve excellence is because "that guy/girl is a genius and I am not".
PS: In the office that justification comes as being an expert: when someone doesn't know how about something, it's because some other person is an expert. When the boss asks the lab manager "how does that WiFi module work?" the answer is "let's call X because she is an expert", when the manager should already know how that works.
I like to think I'm pretty good at what I do, but I could be struggling with something for hours that he could break down in a way that just never occurred to me. So yes, he put in the time, but it was his thought process that made him great, and I'm not convinced that's something that can be taught to great effect.
The thing I've noticed about genius is that it's just part of who you are. It flows out of your pores. You work the kinds of hours and achieve the kinds of things you do, simply because you are driven to do so, and could not be otherwise.
If you're not a genius, then no amount of practice or experience will make you one. You can get better, sure. But to be a genius, you have to start out life as a genius.
Of course, there are many types of genius, in many different areas. But all the geniuses I know fit the above description.
OTOH, our culture does throw around the term much too easily. Many people seem to mistake lots of practice or experience for genius, which is understandable because many geniuses do seem to have a lot of practice and experience. But in a true genius, the cause and effect is reversed for practice and experience versus the results achieved.
I am most definitely not a genius. But I do have a fair amount of practice and experience in certain fields.