Related Clues:

• Clinical study
• Reason to say "1, 2, 3..."
• Run up the flagpole, e.g.
• Hurdle of sorts
• Midterm event
• Do lab work
• Multiple choice, say
• Teacher's unit
• Give a whirl
• Part of 57-Down
• Measuring device
• Reason for cramming
• Marketing event
• Put out a feeler
• Textbook segment