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.