As with other big concepts ("love," "date," "fat-free"), it seems Americans can't quite agree on the definition of sex. Sure, we can all agree on a certain classic act, but according to a recent study from the Kinsey Institute, we can't come to a consensus on what else counts as sex.

The interesting part is that women are less likely than men to consider oral sex or mutual masturbation "having sex." In fact, only 37 to 46 percent of women consider ye olde blow-jays to be "real sex" compared to 44 to 52 percent of men.

Find out why after the jump.

"These data make it clear that general agreement regarding what constitutes having 'had sex' and how sexual partners are counted cannot be taken for granted," said researchers Stephanie Sanders and June Reinisch.

Of course, considering the fact that for many women, hooking up is still something to be ashamed of, we're not surprised that our definition of "what counts" is narrower than a man's. After all, for a lot of dudes, sex is usually something to brag about, whether it's first base or third.

What do you think? Should sex be defined as the old in-out, in-out, or is that definition a little too restrictive? Let us know!