If you're in an older generation and a female calls another female "dude", it may seem strange to you.  It happens all of the time and should be a sign that sexism is less today but a recent study from Psychology of Women Quarterly says subtle, unnoticed daily acts of sexism like that, even women doing it to women, are a concern.

They are not talking about overt sexism, such as the stereotype of union workers catcalling women who walk by, but rather things like calling women "girls" and not calling men "boys" or referring to a collective group as "guys" are subtle forms of sexism that creep into daily interactions. The study claims to helps not only identify which forms of sexism are most overlooked by which sex, but also how noticing these acts can change people's attitudes. 

"Women endorse sexist beliefs, at least in part, because they do not attend to subtle, aggregate forms of sexism in their personal lives," wrote authors Julia C. Becker and Janet K. Swim. "Many men not only lack attention to such incidents but also are less likely to perceive sexist incidents as being discriminatory and potentially harmful for women."

So in order for there not to be discrimination, women need to find too much of it and "see the unseen," the authors note, and make changes, presumably like correcting sentences from other women such as "hey guys, where should we go for lunch?" and noting perhaps the group needs to mix it up by asking, "hey dolls, where should we go to lunch?"

The authors state that women need to be more militant about language - which will just get them invited to lunch less - whereas men need not only to be aware of the sexist behavior or comments, but also to feel empathy for the women targeted, which sounds like men get off pretty easily - is that sexism?

The study goes on to claim differences in the way men and women's beliefs change once they become aware of subtle sexism.   They say their results are consistent with other studies which found that empathy is an effective method for reducing racial and ethnic prejudice.