Related Clues:

• Ulterior motive
• Protractor measurement
• It may be acute
• Go for fish
• Hidden motive
• Polygon corner
• Drop a line from a pier, say
• This can be right
• It may be right
• Seek slyly, with "for"
• One of four in a square
• Geometry measurement
• See 23 Across
• Camera view
• Acute subject?