56 entries under hidden topic. ×
| clandestine(adjective, secret, unknown, sly) | |
| secret(adjective, unknown, spy, concealed) | |
| buried(verb, adjective, secret, unknown) | |
| covert(adjective, secret, unknown, concealed) | |
| surreptitious(adjective, secret, unknown, concealed) | |
| undercover(adjective, secret, unknown, spy) | |
| covered(adjective, obscure, unknown, concealed) | |
| concealed(adjective, secret, unknown, spy) | |
| hole-and-corner(adjective, secret, spy, covert) | |
| cloak-and-dagger(adjective, obscure, unknown, clandestine) | |
| furtive(adjective, obscure, secret, unknown) | |
| hush-hush(adjective, secret, spy, clandestine) | |
| private(adjective, obscure, secret, unknown) | |
| underhand(secret, spy, clandestine, fraudulent) | |
| secluded(adjective, obscure, secret, unknown) | |
| under wraps(expression, adjective, idiom, secret) | |
| clouded(obscure, secret, unknown, concealed) | |
| mysterious(adjective, obscure, secret, unknown) | |
| occult(noun, obscure, secret, unknown) | |
| stealthy(adjective, secret, spy, clandestine) |
For more, visit
Underground on
Power Thesaurus
| APA | Smart Define. (2015). underground thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/underground/thesaurus/synonyms |
| Chicago | Smart Define. 2015. "underground thesaurus" https://smartdefine.org/underground/thesaurus/synonyms (accessed September 23, 2026). |
| Harvard | Smart Define 2015, underground thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/underground/thesaurus/synonyms>. |
| MLA | Smart Define. "underground thesaurus" 3 November 2015. Web. 23 September 2026. <https://smartdefine.org/underground/thesaurus/synonyms> |