1. the permanent closure or shutdown of a business, factory, or operation
Usage: often used in British English; can refer to temporary or permanent cessation
2. the end of broadcasting for the day on a television or radio station
Usage: chiefly British; dated usage

Examples

• The factory announced a closedown due to declining sales.
• Hundreds of workers lost their jobs following the plant closedown.
• The company's closedown was unexpected and left many employees without notice.
• The TV station's closedown occurred at midnight every evening.
• Economic pressures forced the closedown of three retail locations.
• The closedown process took several months to complete.