hush-hush

it was a hush-hush operation, known only to a few.

they had a hush-hush meeting late last night.

the company's new product launch was a hush-hush affair.

there's a hush-hush project happening in the research lab.

he warned me about a hush-hush deal going on.

the negotiations were hush-hush and took place behind closed doors.

it's a hush-hush matter; don't mention it to anyone.

the team worked on the hush-hush software for months.

she hinted at a hush-hush relationship with a colleague.

the investigation into the incident remains hush-hush.

they exchanged hush-hush glances across the room.