face down
facedown
face downwards

The rest of you, face down on the floor, hands behind your back.

All of us were told to stay face down on the floor.

They lay all the men face down on the street.

Instead, they place their cards face down on the table, or playing area.

The others were ordered to get on the ground, face down.

A man and a woman were lying dead on the floor, face down.

At 15 Roberts was finally strong enough to face down his father.

Why, I wouldn't want any better fun than to face down a hundred like him.

Lying on the floor, face down, she felt around at her back.

On the center of the desk was a check, face down.