prone
The patient is in the prone position.
prone
The position where the body is lying on the belly with the face down is called the prone position.
You may be referring to the Trendelenburg tilt.
horizontally directed; compressive stresses
The procedure is performed with the patient lying on her back with her legs in stirrups.
When the body is lying face up, horizontally on one's back, this is called the supine position
The procedure is performed with the patient lying on her back with her legs in stirrups.
Lying is the present participle of lie (to rest horizontally or to speak an untruth).
A double belly is when your upper and lower abdominals form fat and a crease forms horizontally across the naval. This causes fat to build up seperately making two rolls.
side-lying