Adjective
1. not open or public; kept private or not revealed;
"a secret formula""secret ingredients""secret talks"2. 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"3. not openly made known;
"a secret marriage""a secret bride"4. communicated covertly;
"their a secret signal was a wink""secret messages"5. not expressed;
"secret (or private) thoughts"6. designed to elude detection;
"a hidden room or place of concealment such as a priest hole""a secret passage""the secret compartment in the desk"7. hidden from general view or use;
"a privy place to rest and think""a secluded romantic spot""a secret garden"8. (of information) given in confidence or in secret;
"closet information""this arrangement must be kept confidential""their secret communications"9. indulging only covertly;
"a closet alcoholic""closet liberals"10. having an import not apparent to the senses nor obvious to the intelligence; beyond ordinary understanding;
"mysterious symbols""the mystical style of Blake""occult lore""the secret learning of the ancients"11. the next to highest level of official classification for documents