adjective
supine
SOO-pine/ˈsuːpaɪn/
Lying face upward without active resistance.
The older man lies supine on the exercise mat with his face upward.

Etymology
Latin supinus described being turned or thrown backward as well as lying on the back. The English posture sense preserves that backward-facing orientation, with the face upward.
In context
in the supine position the patient should be lying on his or her back with shoulders in line with the hips and the spine should be straight
More examples
- Begin the stretch in a supine position, with your knees bent.
- She rests supine on the grass, watching the clouds.
- The board remains supine while the director ignores its rules.
Forms
supine
supinely adverb — In a passive or unresisting manner.
Similar words
- recumbent
- Describes lying down without specifying which way the face points.
- passive
- Emphasizes accepting events without action, not a physical position.