- 秘密主 mìmìzhǔ Vajrapaniepithet for the bodhisattva Vajrapani, representing the power of all Buddhas and often depicted holding a thunderbolt
- 秘密教 mìmìjiào Tantric Buddhismthe Esoteric school of Buddhism emphasizing ritual and secret teachings
- 秘密证人 mìmìzhèngrén confidential witnessA witness whose identity is kept confidential; someone who provides evidence or information to law enforcement or courts while protected by legal anonymity.