1. secretly cooperating with someone, especially to do something illegal or dishonest
Usage: present participle of ‘collude’

Examples

• The two companies were accused of colluding to fix prices.
• She suspected her colleagues of colluding against her.
• The investigation revealed that officials were colluding with criminals.
• They were caught colluding to cheat on the exam.
• The competitors denied colluding to divide the market.
• Evidence suggested the witnesses were colluding on their testimony.