In North America a closed shop is a business or industrial factory in which union membership (often of a specific union and no other) is a precondition to employment.
closed shop. Any place of work, such as a factory or an office, where all workers within a section must belong to a single, officially recognized trade union.
closed shop. Any place of work, such as a factory or an office, where all workers within a section must belong to a single, officially recognized trade union.