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

See also: covert

Encyclopedia: Undercover

• troop transport
• trooper
• troops
• troopship
• Tropaeolaceae
• Tropaeolum
• Tropaeolum majus
• Tropaeolum minus
• Tropaeolum peregrinum
• trope
• trophic
• trophobiosis
• trophoblast
• trophoblastic
• trophoblastic cancer
• trophotropic
• trophotropism
• trophozoite
• trophy
• trophy case
• trophy wife
• tropic
• Tropic of Cancer
• Tropic of Capricorn
• tropical