hush-hushˌhush-ˈhush / $ ˈ‧ ‧/ adjective informal 
Examples
Everything was very hush-hush.► see thesaurus at secret
ExamplesEXAMPLES FROM OTHER DICTIONARIES
Thesaurus- 'The Manhattan Project' was the insiders' name for the hush-hush project.
- His death was really hush-hush. It was so covered up that you wondered if it wasn't a suicide.
- The date and location of the operation were very hush-hush.
- And this is meant to be hush-hush.
- As a matter of fact it was rather a hush-hush sort of business.
- Some sort of hush-hush oceanography, probably for oil.
- There was a hush-hush meeting with Eliot and I was to keep out of the way.
- What you two so impertinently called my hush-hush experi-ment.
THESAURUS► secret
very secret: known about by only a few people, who have agreed not to tell anyone else: · a secret meeting place· The details of the proposal must remain secret.
► confidential used about information, especially in business or government, that is secret and not intended to be shown or told to other people: · a highly confidential report· Employees’ personal details are treated as strictly confidential.
► classified used about information that the government has ordered to be kept secret from most people: · He was accused of passing on classified information to the Russians in the 1950s.
► sensitive used about information that is kept secret because there would be problems if the wrong people knew it: · A teenager managed to hack into sensitive US Air Force files.
► covert [only before noun] used about things that are done secretly, especially by a government or official organization: · a CIA covert operation
► undercover [usually before noun] used about things that are done secretly by the police in order to catch criminals or find out information: · Detectives arrested the suspect after a five-day undercover operation.
► underground an underground organization or newspaper is one that operates or is produced secretly and opposes the government: · Her father was a member of the underground resistance movement in France during World War II.
► clandestine secret and often illegal or immoral: · clandestine meetings· his involvement in a clandestine operation to sell arms to Iran· a clandestine love affair
► hush-hush informal used about information or activities that are kept officially secret: · He was put in charge of some hush-hush military project.· I’ve no idea what he does – it’s all very hush-hush.
Longman Language Activatorsecret information/plans/places/activities► secret if something is secret , not many people know about it, and they agree not to tell anyone else about it: · The letter was written in a secret code.· Secret documents containing details of Britain's defence plans have been stolen.· The president's schedule is secret, but there is speculation that he will visit UN troops in the area.remain/stay secret: · I hope you see how vital it is that our conversation remains secret.top secret (=when an official document, piece of information etc is very secret): · The experiments were top secret.secret ballot (=a secret vote): · The Leader of the House will be selected by secret ballot.
► confidential confidential information is known only by a few official people, and must not be told to anyone else, for example because it contains military secrets or private details about people: · We hold confidential records on each employee.· Always protect confidential files by locking them with a password.· An employee secretly gave confidential memos to the press.highly confidential (=very confidential): · The information we received is of a highly confidential nature and relates to national security.
► classified classified information or documents are ones that the government has ordered to be kept secret: · There is evidence that Huang had access to classified information.· Only licensed companies are eligible to receive, store, or send classified material.
► sensitive information or documents that are sensitive are likely to cause problems or embarrassment if they are made public and therefore they are kept secret: · A teenager used his personal computer to break into sensitive US Air Force files. · Your competitors may have access to the company intranet, so never discuss commercially sensitive issues on-line.highly sensitive: · The minister admitted that highly sensitive documents had been leaked to the press.
► covert done secretly, especially by a government or official organization, often involving breaking the law: · The chief investigator resigned, amid allegations of covert and probably illegal operations.· The abuse of residents in the home was confirmed by covert video surveillance.
► undercover working secretly - use this about the activities of the police, the army etc: · Six members of a drug-smuggling gang were arrested after an 18-month undercover police operation.· The unit is equipped to deal with a variety of situations, including undercover surveillance.
► be veiled in secrecy/shrouded in secrecy/cloaked in secrecy if something is veiled , cloaked , or shrouded in secrecy , very little is known about it and it seems very mysterious: · In Japan, the private lives of the Emperor and his family were once veiled in secrecy.· The President's exact itinerary was cloaked in secrecy for security reasons.· This ground-breaking work is shrouded in secrecy on the instruction of the company's lawyers.
► hush-hush informal kept officially secret: · His death was really hush-hush. It was so covered up that you wondered if it wasn't a suicide.· 'The Manhattan Project' was the insiders' name for the hush-hush project.
► cloak-and-dagger use this about methods and activities that involve a lot of secrecy, especially when this seems unnecessary: · He was arrested after a cloak-and-dagger operation involving the CIA and MI6.
Everything was very hush-hush.► see thesaurus at secret