Supine

1. Lying on its back. Synonym: reclined Antonyms: prone, prostrate
2. (of the hand, forearm or foot) turned facing toward the body; with the thumb outward or the big toe upward.
3. (figuratively) Reluctant to take action due to indifference or moral weakness; apathetic or passive towards something. Synonyms: passive, peaceful, lazy, lethargic, listless
4. (rare, now poetic) Inclining or leaning backward; inclined, sloping. Synonyms: inclined, sloping

Antonyms

• nonsupine
• prone