Ichidan/ru-verb

1. to turn over (face down); to lay face down; to lay upside down
2. to point downwards (eyes, head, etc.); to cast down (eyes)
3. to lie (one's body) face down; to lie flat (on the ground)
4. to conceal; to hide; to keep secret; to place in hiding (e.g. troops for an ambush)

-ru Godan/u-verb

5. to lie down; to retire; to go to bed (with an illness) (usu. 臥せる)