Security confinement was the action of confining a prisoner to the brig of a starship.
In 1968, the time traveling USS Enterprise intercepted the transporter beam of Gary Seven. Ordered to security confinement, Seven resisted by attacking a security team, Lieutenant Commander Spock, and Chief Engineer Montgomery Scott before being stunned by Captain James T. Kirk. As Seven was escorted away from the transporter room to security confinement, Kirk ordered Doctor Leonard McCoy to quickly perform a medical analysis to determine if Seven was Human or not. Seven later escaped confinement by using a servo to disable the brig's force field and stun his guard. (TOS: "Assignment: Earth")