To use a blackboard to assist in an informal discussion.
A large flat surface, finished with black slate or a similar material, that can be written upon with chalk and subsequently erased; a chalkboard.
In dodgeball and related games, the area where players who have been struck by the ball are confined.
Confinement in a jail.
A kind of sandbox for running a guest operating system instance.
A place or institution for the confinement of persons held against their will in lawful custody or detention, especially (in US usage) a place where people are held for minor offenses or with reference to some future judicial proceeding.
The condition created by the requirement that a horse claimed in a claiming race not be run at another track for some period of time (usually 30 days).
To imprison.