- torpor (n.)
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- "lethargy, listlessness," c. 1600, from Latin torpor "numbness, sluggishness," from torpere "be numb, be inactive, be dull," from PIE root *ster- (1) "stiff, rigid, firm, strong" (source also of Old Church Slavonic trupeti, Lithuanian tirpstu "to become rigid;" Greek stereos "solid;" Old English steorfan "to die;" see stereo-).