Adjective undercover has 1 sense
- clandestine, cloak-and-dagger, hole-and-corner, hugger-mugger, hush-hush, on the quiet, secret, surreptitious, undercover, underground - conducted with or marked by hidden aims or methods; "clandestine intelligence operations"; "cloak-and-dagger activities behind enemy lines"; "hole-and-corner intrigue"; "secret missions"; "a secret agent"; "secret sales of arms"; "surreptitious mobilization of troops"; "an undercover investigation"; "underground resistance"
Antonyms: overt, open (indirect, via covert)
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