acuteness

The quality of being acute or pointed.

the acuteness of an angle

Of the senses or feelings: the faculty of precise discernment or perception; sensitiveness.

By acuteness of feeling, we perceive small objects or slight impressions.

By acuteness of intellect, we discern nice distinctions.

Of sounds: shrillness; high pitch.

Violence of a disease, which brings it speedily to a crisis.

At the time, I set it down to some idiosyncratic, personal distaste, and merely wondered at the acuteness of the symptoms; but I have since had reason to believe the cause to lie much deeper in the nature of man, and to turn on some nobler hinge than the principle of hatred.

Shrewdness, quickness of mind.