TORONTO - Casual sex isn't just called casual sex any more.
A University of Ottawa researcher says young people have their own codes to describe sexual encounters outside of committed relationships.
Jocelyn Wentland, a doctoral student in experimental psychology, looked at the various types of casual-sex relationships among people aged 18 to 27 and how they are termed.
"We now have names to describe these things in ways that wasn't the case say 20, 30 years ago," Wentland said Thursday.
The four most popular terms used by those in the focus groups included "booty call," "friends with benefits" and "one-night stand." The remaining term has a profanity in it, but can be politely translated as "sex" buddy.
All the terms used to describe the encounters have subtle nuances of meaning, said Wentland.
For instance, a booty call is an invitation from someone you already know who wants to meet for impromptu sex, according to the study's authors.
The booty call is made "usually by text and often late at night," said Wentland, adding alcohol may also be involved.
On the other hand, the one-night stand is usually the classic case of two people who meet at a bar and then hook up for the night, she explained.
"Somebody probably sleeps over but they leave right in the morning. There's no breakfast, there's no hanging around."
As for friends with benefits, they are people who were friends before they became sexually involved. Those relationships, Wentland says, are the most complicated.
See Hollywood's modern casual sex films ... story continues below
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The friends might be part of a group and not want the others to know about their sexual relationship, she said.
How relationships were defined depended on the frequency of sexual contact, how much personal information is shared, and emotional attachment, among other things.
Wentland's study looked at factors such as how the partners knew each other, whether they added each other to Facebook, and if they discussed the ending of the relationship.
Her study showed both males and females know the rules of conduct for each relationship type.
Other terms that were discussed during the study that did not make the top four included: boy toy, fling, fooling around and no strings attached.
Wentland's article, "Taking Casual Sex Not Too Casually: Exploring Definitions of Casual Sexual Relationships" is published in the Canadian Journal of Human Sexuality.