hush-hush

Adjective

WORDNET DICTIONARY

hush-hush(s = adj.all) clandestine, cloak-and-dagger, hole-and-corner, hugger-mugger, 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"

hush-hush, adj. colloq. (esp. of an official plan or enterprise etc.) highly secret or confidential.

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