keep mum
stay mum

The guy I talked to knows how to keep mum.

I'd be sure of my dough if I kept mum.

Better to play it safe, he thought, and keep mum.

Talk frankly, and I'll give you my word to keep mum.

Company policy, which he does his best to observe, is to keep mum on politics.

"Well, just remember to keep mum if you do get the chance," she said.

He is also not allowed to keep mum when someone asks him a question.

I'm telling you this, so as you'll know to keep mum.

I've taken your word for it that the prof will keep mum.

Why on earth did he think it was possible to keep mum for five days?"

I'll tell you all I know; but remember, the sheriff wants it kept mum.

Their game was to admit certain facts, in order to keep mum on others.

I was afraid, sir - it seemed best just to keep mum.

Why, then, do some women keep mum when illness enters their lives?

Of course, we keep mum about it, so as not to become a test case."

Right now, the thing to do is keep mum.

But if you stay, keep mum and all that - they won't know anything.

There was no other course than to stick with the mob and keep mum.

It don't make any difference what happens, we got to keep mum.

They're afraid he will get wise to them and demand a cut to keep mum.

"I wanted you to keep mum on the whole business until I'd seen the commissioner.

The men themselves have apparently kept mum, too, despite intense interrogation.

He kept mum for almost two years after he became head of the Union.

They say the lesson was for the nominee to keep mum on his views.

Five thousand dollars in a paper bag, and then he asks you to keep mum?