Related Clues:

• Not weighing much
• Start out
• Make the first move
• Onset
• Dive in
• Many solvers do it here
• Easy to lift
• Brief shock
• Get cracking
• All the clues in this puzzle do this with 36-Across
• Get the ball rolling
• Found
• Button word, sometimes
• Spur, as a chain reaction
• Square on many board games