1. The quality of being acute or pointed; sharpness; as, the acuteness of an angle.
2. The faculty of nice discernment or perception; acumen; keenness; sharpness; sensitiveness; applied to the senses, or the understanding. By acuteness of feeling, we perceive small objects or slight impressions: by acuteness of intellect, we discern nice distinctions. Perhaps, also, he felt his professional acuteness interested in bringing it to a successful close. (Sir W. Scott)
3. Shrillness; high pitch; said of sounds.
4. (Science: medicine) violence of a disease, which brings it speedily to a crisis.
Synonym: penetration, sagacity, keenness, ingenuity, shrewdness, subtlety, sharp-wittedness.
A quick and penetrating intelligence; he argued with great acuteness; I admired the keenness of his mind.