Ebauche

An ebauche is a basic movement supplied by a specialist maker for a watch brand to finish, modify, and put into its own watches.

Many respected watches use ebauche-based movements, often refined by the brand. They tend to be well understood by watchmakers and easy to service, which can be a practical advantage.

An ebauche-based movement isn't a mark against a watch, but buyers sometimes value in-house calibers more, and the difference can show up in secondary prices.