Definitions by RICHvcl
Tri-Sci
A rendition of the widely known sexual act known as "scissoring", which typically consists of two participants. However, when a third person daringly decides to join in, it is referred to as the "Tri-Sci", due to the positioning/layout of the three participants and their genitalia. This act can be performed by three females, two males and one female, or three males. Although many have attempted the Tri-Sci with two females and one male, it has proved to be an impossible task.