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)

• handlist
• handlists
• hand-loom
• hand-looms
• hand lotion
• hand lotions
• handmade
• handmaid
• handmaiden
• handmaidens
• handmaids
• hand mating
• hand-me-down
• hand-me-downs
• hand-mill
• hand-mills
• hand-off
• hand-offs
• magnetic cards
• magnetic chuck
• magnetic chucks
• magnetic confinement
• magnetic core
• magnetic cores
• magnetic curves