linchpin /linchˈ or linshˈpin/

1. A pin used to keep a wheel on its axle
2. A person or thing essential to a plan, organization, etc (figurative)

• make the pace
• make the rounds
• make the running
• make things hum
• make tick
• make time
• make tracks
• make tracks for
• makeunder
• make unready
• make up
• make-up
• make up leeway
• make up one's mind
• make-ups
• make up to
• make use of
• make war
• make water
• make waves
• make way
• make-weight
• make-weights
• make whoopee
• make wing