Acuteness

Noun

1. The quality of being acute or pointed.

   "the acuteness of an angle"

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

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

3. Of sounds: shrillness; high pitch.
4. Violence of a disease, which brings it speedily to a crisis.
5. Shrewdness, quickness of mind.