hush-hush

[ huhsh-huhsh ]

/ ˈhʌʃˌhʌʃ /

highly secret or confidential: a hush-hush political investigation.

Origin of hush-hush

First recorded in 1915–20; reduplication based on hush

Escorting is big business on the straight side too, only more of a hush-hush operation.

Risky Business or None of Your Business? Gay XXX Films and the Condom Question |Aurora Snow |November 1, 2014 |DAILY BEAST
She hesitated to explain any further because, she said, “TLC has kind of told us to hush-hush.”

The Shocking Rise and Fall of ‘Honey Boo Boo’ |Kevin Fallon |October 24, 2014 |DAILY BEAST
She's willing to speak about things people might to keep on the down-low or hush-hush.

Sex Trafficking Survivor’s Inspiring Political Run in Portland, OR |John Avlon |April 3, 2012 |DAILY BEAST
First, the government stepped in, trying to hush-hush the whole thing; but too late.

Of Stegner's Folly |Richard S. Shaver

Mr. Atkins explained that naturally the affair was hush-hush.

In the Cards |Alan Cogan
They are not half so mysterious as you are with that hush-hush expression on your innocent countenance.

The Professor's Mystery |Wells Hastings
Our Hush-hush Department seems to have grown very lax of late.

Punch, or the London Charivari, Vol. 158, March 3rd, 1920 |Various
She was a "hush-hush" ship—one of the wonders of the Navy still.

The Grey Room |Eden Phillpotts

hush-hush

informal (esp of official work, documents, etc) secret; confidential