1. people or things that are essential to the success or functioning of something
Usage: figurative use; plural of linchpin
2. metal pins that pass through the end of an axle to keep a wheel in position
Usage: mechanical/automotive; literal use; plural of linchpin

Examples

• The experienced teachers are the linchpins of our school’s success.
• Small businesses are often considered the linchpins of the local economy.
• Without these key employees, who serve as linchpins, the project would fail.
• The mechanic replaced the worn linchpins on the wagon wheels.
• These linchpins hold the entire wheel assembly together.
• The team’s star players are the linchpins of their championship hopes.
• Strong family relationships are the linchpins of a stable community.