Some girl at my husband's work called him that, and I was just wondering what it meant. I think I know, is it because he's not gay but has a really good sense of style, brands, clothing, stuff like that?
It's a straight guy who acts, dresses, and/or looks gay. He might be obsessed with self-image like a girl, or work on his hair constantly, or say things like a girl, etc. He might just seem gay - but he's not.
A very straight male (in fact I suspect most metrosexuals do not even care for the company of other men) who cares a lot about his appearance. This means he is very stylish and expects his female significant other to be stylish as well. Often confused for a gay guy because he cares a lot about his appearance.