Synonyms to top-secret

secret, abstract, abstruse, arcane, arcanum, beclouded, behind the curtain, behind the scenes, blind, buried, by stealth, cabala, cabalistic, camouflaged, censored, clandestine, classified, classified information, close, closed, closemouthed, clouded, concealed, confidence, confidential, confidential communication, confidentially, covered, covert, cryptic, cryptographic, dark, deep, deep-seated, devious, discreet, disguised, eclipsed, encrypted, enigma, enigmatic, esoteric, esoterica, evasive, furtive, furtively, genitals, guarded secret, heavy, hermetic, hermetics, hid, hidden, hole-and-corner, hugger-mugger, hush-hush, immanent, imperceptible, implanted, implicit, in a cloud, in a fog, in eclipse, in purdah, in secret, in the wings, inalienable, incommunicado, incomprehensible, indiscernible, indwelling, infixed, ingrained, inherent, inner, insensible, internal, intrinsic, invisible, inward, inwrought, irreducible, latent, lonesome, mysterious, mystery, mystery of mysteries, mystical, obfuscated, obscure, obscured, occult, on the sly, out of sight, out-of-the-way, parts, personal matter, private, privat