Casual sex

noun

sexual relations not involving a love relationship, esp. brief encounters or an encounter on one occasion
Examples

Schools advise youngsters on the dangers of casual sex.
Contemporary Examples

Complications arise when Jules engages in some casual sex with Paul, blurring the familial lines for all parties involved.
Prepping for the Oscars on DVD Marlow Stern January 20, 2011

casual sex doubled between 2004 and 2008, another survey reported.
Priest Sex-Tape Horror Dom Phillips April 25, 2010

Eleanor Maticka-Tyndale, et al. “casual sex Among Australian Schoolies.”
It’s High Time for Conception: Studies Show Peak Times, Weather for Sex Anneli Rufus December 26, 2011

People worked all hours, often addled with booze and drugs, and casual sex was readily available.
Murdoch on the Rocks: How a Lone Reporter Revealed the Mogul’s Tabloid Terror Machine Clive Irving August 24, 2014

They “hook up” in a manner that makes the casual sex of the 1960s seem like an arranged marriage in Oman.
Up to a Point: They Made Me Write About Lena Dunham P. J. O’Rourke December 12, 2014

She just thinks that ideal life experience involves a regimented, specific schedule of studying and casual sex.
The New Season of ‘Girls’ Is Just Good. Can We Handle That? Kevin Fallon January 8, 2014

The problem with casual sex with people in close proximity is that they never really go away.
Sex in the Time of GPS Clark Harding January 31, 2010

From casual sex to Death By Unga Bunga, here are the wackiest names of the fest.
Craziest SXSW Band Names: Perfect Pussy, Death By Unga Bunga, and More Marlow Stern March 7, 2014

casual sex had never interested me before; I had always been a bit of a prude.
Sugar Daddy Dating Sites: Helen Croydon on Her Guilty Fantasy Helen Croydon May 10, 2013