- sagacity (n.)
- c.1500, from Old French sagacité, from Latin sagacitatem (nominative sagacitas) "quality of being acute," from sagax (genitive sagacis) "of quick perception," related to sagus "prophetic," sagire "perceive keenly," from PIE root *sag- "to track down, trace, seek" (cf. Old English secan "to seek;" see seek). Also used 17c.-18c. of animals, meaning "acute sense of smell."