Dubplate
An exclusive, "one-off" record pioneered by Jamaican sound systems but also used by drum and bass and other dance music artists, DJs and soundsystems. Dubplates will often be either unreleased recordings (which may or may not end up being made available to the general public) or exclusive versions or remixes of existing recordings.
Dubplates are traditionally 10 inches in diameter. Because they are made of acetate rather than vinyl, they have a limited life-span.
Reggae soundsystems will often compete with each other to acquire the most imaginative or unusual dubplates in order to win soundclashes with their rivals.