1. kept secret or done secretively, especially because illicit

Examples

• The rebels held clandestine meetings in the basement.
• She discovered her husband’s clandestine affair through his phone messages.
• The government conducted clandestine operations overseas.
• They arranged a clandestine exchange of documents at midnight.
• The clandestine organization operated without public knowledge.
• His clandestine activities were finally exposed by the press.