clandestine

UK: /klænˈdɛstɪn/ US: /klænˈdɛstɪn/ ,(klan des′tin)

WordReference Random House Learner's Dictionary of American English © 2026

clan•des•tine /klænˈdɛstɪn/   adj. 

1. done in secrecy:
   a clandestine meeting of conspirators.

clan•des•tine•ly, adv. 
clan•des•tine•ness, clan•des•tin•i•ty /ˌklændɛsˈtɪnɪti/  n. [uncountable]

WordReference Random House Unabridged Dictionary of American English © 2026

clan•des•tine  (klan des′tin), adj. 

1. characterized by, done in, or executed with secrecy or concealment, esp. for purposes of subversion or deception;
   private or surreptitious:
   Their clandestine meetings went undiscovered for two years.

• Latin clandestīnus, equivalent. to *clande, *clamde, variant of clam secretly (with -de adverb, adverbial particle) + -stīnus, probably after intestīnus internal; see intestine
• 1560–70

clan•des′tine•ly, adv. 
clan•des′tine•ness, clan′des•tin′i•ty, n. 
Synonyms

hidden, underhand, confidential, illicit.

Collins Concise English Dictionary © HarperCollins Publishers::

clandestine / klænˈdɛstɪn/ adjective

1. secret and concealed, often for illicit reasons; furtive

Etymology: 16th Century: from Latin clandestīnus, from clam secretly; related to Latin celāre to hide

clanˈdestinely adverb