Some [brutes] show that nice sagacity of smell.Cowper.
Natural sagacity improved by generous education.V. Knox.
Syn. -- Penetration; shrewdness; judiciousness. -- Sagacity, Penetration. Penetration enables us to enter into the depths of an abstruse subject, to detect motives, plans, etc. Sagacity adds to penetration a keen, practical judgment, which enables one to guard against the designs of others, and to turn everything to the best possible advantage.