Having a downward inclination or slope.
Of the hand, forearm or foot: turned facing away from the body; with the thumb inward or big toe downward.
Lying face downward.
Predisposed, liable, inclined.
To place in a prone position, to place face down.
Bending away from the perpendicular; recumbent.
Capable of being reclined, or moved into a more horizontal position.