Clandestine often substitutes for secret and covert, and it is commonly applied to actions that involve secrecy maintained for an evil, illicit, or unauthorized purpose, as in "clandestine activities pursued …

CLANDESTINE definition: characterized by, done in, or executed with secrecy or concealment, especially for purposes of subversion or deception; private or surreptitious. See examples of …

CLANDESTINE definition: 1. planned or done in secret, especially describing something that is not officially allowed: 2…. Learn more.

Definition of clandestine adjective in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

Feb 13, 2026 · Adjective clandestine (comparative more clandestine, superlative most clandestine) Done or kept in secret, sometimes to conceal an illicit or improper purpose. Synonyms: covert, …

held or done in secrecy or concealment, esp. for purposes of subversion or deception; stealthy or surreptitious: clandestine meetings.

WordReference Random House Unabridged Dictionary of American English © 2025 clan•des•tine (klan des′ tin), adj. characterized by, done in, or executed with secrecy or concealment, esp. for purposes …

Clandestine definition: Kept or done in secret, often to conceal an illicit or improper purpose.

Something that is clandestine is hidden or kept secret, often because it is illegal.

Use the adjective clandestine to describe something that is done in secret, like your clandestine attempts to steal your brother's Halloween candy. Clandestine, an adjective imported from Latin, …