Noah Webster
Sagacious
SAGA'CIOUS, adjective [Latin sagax, from sagus, wise, foreseeing; saga, a wise woman; sagio, to perceive readily. The latter signifies wise, prudent, sage, and an essay, which unites this word with seek, and Latin sequor.]
1. Quick of scent; as a sagacious hound; strictly perhaps, following by the scent, which sense is connected with Latin sequor; with of; as sagacious of his quarry.
2. Quick of thought; acute in discernment or penetration; as a sagacious head; a sagacious mind.
I would give more for the criticisms of one sagacious enemy, than for those of a score of admirers.