1. Conducted with or marked by hidden aims or methods
   "clandestine intelligence operations"
   - cloak-and-dagger, hole-and-corner, hugger-mugger, hush-hush, secret, surreptitious, undercover, underground

See also: covert

Encyclopedia: Clandestine

• helleri
• Hellespont
• hellfire
• hellgrammiate
• hellhole
• hellhound
• hellion
• hellish
• hellishly
• Hellman
• hello
• helluva
• helm
• helmet
• helmet orchid
• helmet-shaped
• helmeted
• helmetflower
• Helmholtz
• helminth
• helminthiasis
• helminthic
• helminthology
• Helminthostachys
• Helminthostachys zeylanica