lying
寝そべり 寝そべる 横臥 横になる 寝転がる うつぶせ うつ伏せ
Lying down flat on a surface, mainly being supported by the back, side or the stomach.
(Grammatical Note: Lying is the correct term to describe someone's posture. "Laying" should only be used when something is performing the action of laying something else down.)
See also
The following tags are aliased to this tag: laying, laying_down, and lying_down (learn more).