Supine

Lying on the back, or with the face upward; -- opposed to prone.

Leaning backward, or inclining with exposure to the sun; sloping; inclined.

Negligent; heedless; indolent; listless.

A verbal noun; or (according to C.F.Becker), a case of the infinitive mood ending in -um and -u, that in -um being sometimes called the former supine, and that in -u the latter supine.