linchpin
noun/ˈlɪntʃpɪn/
/ˈlɪntʃpɪn/
(also lynchpin)
- a person or thing that is the most important part of an organization, a plan, etc., because everything else depends on them or it
- Nurses are the linchpin of the health service.
Word Originlate Middle English: from Old English lynis (in the sense ‘linchpin’) + pin.
Check pronunciation:
linchpin