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)

• alleviated
• alleviates
• alleviating
• alleviation
• alleviations
• alleviative
• alleviator
• alleviators
• alleviatory
• alley
• alleycat
• alleycats
• alleyed
• alley-oop
• alleys
• alley-taw
• alley-tor
• alleyway
• alleyways
• allez-vous-en
• All-father
• all fingers and thumbs
• all-fired
• all-firedly
• all-fives