Flying Scissor Slam (abbreviated F.S.S.) is an act commonly carried out by lesbian women. It involves, as the name suggests, the sexual act of scissoring. However with the F.S.S. scissoring takes place when one or both partners jump and meet the other one in the air (hence flying). This results in a collision of the genital area (and thus slam). The origin of the name is believed to have been traced back to university students in North America, most likely Canada. Whether or not they are the inventors is still unknown.
"We totally flying scissor slammed last night."