The definition of supine is laying on the back facing upward or showing a feeling of indifference.(adjective)
See supine in Webster's New World College Dictionary
Origin: L supinus, prob. akin to sub-: see sub-
See supine in American Heritage Dictionary 4
Origin: Middle English supin, Latin verbal noun
Origin: , from Late Latin supīnum (verbum), (verb) lying on its back, (verb) going back
Origin: , neuter of Latin supīnus; see upo in Indo-European roots.
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