[1] : The Collaborative International Dictionary of English v.0.48

clandestine \clandes"tine\, a. l. clandestinus, fr. clam
   secretly; akin to celare, e. conceal: cf. f. clandestin.
   conducted with secrecy; withdrawn from public notice, usually
   for an evil purpose; kept secret; hidden; private; underhand;
   as, a clandestine marriage. --locke.

   syn: hidden; secret; private; concealed; underhand; sly;
        stealthy; surreptitious; furtive; fraudulent. --
        clandes"tinely, adv. -- clandes"tineness, n.
        1913 webster
see also:
clandes"tinely clandes"tineness 

[2] : WordNet (r) 2.0

clandestine
     adj : 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" syn: cloak-and-dagger, hole-and-cornera,
            hugger-mugger, hush-hush, on the quietp, secret,
            surreptitious, undercover, underground
see also:
cloak-and-dagger hole-and-cornera hugger-mugger hush-hush on the quietp secret 
surreptitious undercover underground 

[3] : Moby Thesaurus II by Grady Ward, 1.0

26 moby thesaurus words for "clandestine":
   back-door, backstairs, covert, feline, furtive, hidlings,
   hole-and-corner, hugger-mugger, privy, quiet, shifty, skulking,
   slinking, slinky, sly, sneaking, sneaky, stealthy, surreptitious,
   under-the-counter, under-the-table, undercover, underground,
   underhand, underhanded, unobtrusive

[4] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

clandestine. that which is done in secret and contrary to law. 
     2.generally a clandestine act in case of the limitation of actions will 
prevent the act from running. a clandestine marriage is one which has been 
contracted without the form which the law has prescribed for this important 
contract. alis. princ. 543 

Clandestine >> C Words
Clandestine, definition of term: Clandestine
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Clandestine Ope >> C Words
Clandestine Ope, definition of term: Clandestine Ope
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