1. to form or join a labor union
Usage: British spelling
2. to cause workers to form or join a labor union
Usage: British spelling

Examples

• The factory workers decided to unionise for better working conditions.
• Management tried to prevent employees from unionising.
• She helped unionise the retail workers in her district.
• The company feared that their workforce would unionise.
• It took months to successfully unionise the entire department.
• The campaign to unionise the restaurant staff gained momentum.