1. Acuteness of mental discernment; aptitude for investigation or discovery; keenness and soundness of judgement in the estimation of persons and conditions, and in the adaptation of means to ends; penetration, shrewdness: Floyd was known for his sagacity by having profound knowledge and understanding, coupled with foresight and good judgment.
2. Etymology: from Middle French sagacité which came from Latin sagacitatem, sagacitas, "quality of being acute", from sagax, sagacis, "of quick perception", related to sagus, "prophetic", and sagire, "to perceive keenly".