hush hush

/ˈhʌʃ ˌhʌʃ/
adjective
  1. Secret and not to be discussed or revealed.
    • They held a hush-hush meeting to discuss the merger.
    • The project is so hush-hush that even the employees don't know about it.
    • The details of the new product are still hush-hush.
Antonyms
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