acuteness

adjective

1. having a sharp point
2. keen or quick of mind; shrewd
3. sensitive to impressions: acute hearing
4. severe and sharp, as pain, jealousy, etc.
5. severe but of short duration; not chronic: said of some diseases
6. very serious; critical; crucial: an acute shortage of workers
7. shrill; high in pitch
8. of less than 90 degrees: an acute angle
9. intensive (sense )