Related Clues:

• Incisive
• Dense
• Sharp, as vision
• Finely honed
• Very sharp
• Much more than mere
• Extreme, as pain
• Not quite right?
• Very perceptive
• Less than right?
• Type of triangle
• Like angles less than 90 degrees
• Not exactly insightful
• Lacking in insight
• Less than 90 degrees, in geometry