Synonyms for secret

noun information known only to a special group

noun something that baffles understanding and cannot be explained

adjective not open or public; kept private or not revealed

adjective conducted with or marked by hidden aims or methods

adjective not openly made known

adjective communicated covertly

adjective not expressed

adjective designed to elude detection

adjective hidden from general view or use

adjective (of information) given in confidence or in secret

adjective indulging only covertly

adjective having an import not apparent to the senses nor obvious to the intelligence; beyond ordinary understanding

adjective the next to highest level of official classification for documents