You had sex last night – or did you? This depends on whom you ask, as well as what you stand to gain, or lose, by calling it sex. With so many people having their own definitions of what it means to “have sex,” what types of sexual experiences make the cut?

People do not share the same clear, unbiased definition of what constitutes sex. This was exemplified when former President Bill Clinton explained his relationship with Monica Lewinsky as one where: “I did not have sexual relations with that woman.” This statement launched a fury of discourse around what it really means to have sex.

Yet there are plenty of others scenarios that beg equal scrutinizing. Here are just a few...

a. The extramarital affair where no more than oral sex is exchanged.

b. Intimacy where only sex toys are used for pleasuring.

c. A person exchanging sexual thoughts with a stranger online.

Would you say any of these persons had “sex?”

While probing such matters, research conducted by the Kinsey Institute in 1999 found that 99.5 percent of respondents regarded intercourse as sex, while only 40 percent believed oral sex to be sex.

Research efforts since then, largely involving respondents reacting to a list of sexual behaviors and labeling them as sex or not, have found similar assessments in the U.S., Canada, Australia and the U.K. Very few respondents regard kissing as sex.

Taking a deeper look at how people define sex, a 2007 study at the University of Kansas asked 51 women and 49 men to rate experiences as “almost but not quite sex” or “just barely sex.” As expected, there was a great deal of ambiguity in the participants’ definitions of sex.

What threw academics for a loop was the fact that even when participants were able to define sex, their definition was inconsistent with their own descriptions of whether their own behavior classified as “sex” or not. Basically, an individual’s definition changed based on the consequences involved in using the label “sex” and their perceptions of the sexual exchange.

Consider that one survey respondent described a scenario where she and her partner engaged in breast play and oral sex. Intercourse was attempted, but stopped because it hurt. Despite recognizing that she had engaged in intercourse, she reported being unsure if she’d ever had sex and still considered herself a virgin.

So what are some of the criteria that impact what constitutes sex for an individual? The body of research has highlighted a number of factors that play into the assessment, including:

1. The Journal of Sex Research found that people are likelier to count an encounter as sex if it resulted in orgasm.

2. Oral sex is likelier to be labeled sex by the recipient than by the giver.

3. Study participants at the University of Kansas admitted that labeling an interaction as sex can depend on what they were thinking about or who they were discussing the matter with. Sexologists also see technology, the media, and laws as all further influencing what gets labeled as sex.

4. Was there consent or alcohol involved? Individuals may be less willing to label an act as sex if they were intoxicated or unable to agree to relations.

5. Sexual orientation often plays a role. A person who identifies as lesbian, for example, may not consider an intimate exchange with a male as sex because the behavior is inconsistent with her sexual orientation.

6. Seeing an experience as sex or not can have a lot to do with whom you’re trying to please. As highlighted in an episode of “The Secret Life of the American Teenager,” if you don’t believe that oral sex is sex, then everyone wins.

Ultimately, what defines sex for an individual may boil down to the costs versus benefits of labeling it. The University of Kansas study highlighted the fact that people adjust their definition from one situation to the next. Their motivation for this is to realize a positive result and advance their own particular interests.

Those who don’t want to label an experience as sex are often doing so to avoid negative self-evaluations. For women, this may include the desire to see themselves as virgins. For men, this may be due to not wanting to have sex with the wrong person or harm a friendship.

For young people, the motivation to not define a situation as sex may be due to having taken a virginity pledge, having conservative religious beliefs, and/or having received abstinence-only sex education. Research conducted at Harvard in 2006 found that 11 percent of adolescents who said that they had sexual intercourse denied the act just one year later. Those retracting their experience were likelier to have become born-again Christians or have taken a virginity pledge.

Alternatively, people may want to claim an ambiguous experience as sex if they want to expand their sexual resume, especially in claiming “been there, done that” status. Such a desire is likelier in scenarios involving first sexual experiences or daring experiences like a threesome.

It’s important for educators and health-care professionals to know how people define sex since this has major implications. A person’s definition of sex influences abstinence and safer sex efforts, questions asked during a medical exam, and their risk-taking behaviors.

It also affects what is being understood when lovers communicate about their relationships or sexual histories. It impacts the discussion had between a parent and youth on values around sex and intimate relationships. In any case, it shakes our foundation of what is “real,” which opens a whole other can of worms...

Dr. Yvonne K. Fulbright is a sex educator, relationship expert, columnist and founder of Sexuality Source Inc. She is the author of several books including, "Touch Me There! A Hands-On Guide to Your Orgasmic Hot Spots."

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