linchpin

Meaning

Noun

1. A pin inserted through holes at the end of an axle or shaft, so as to secure a wheel or shaft-mounted device.
2. A central cohesive source of stability and security; a person or thing that is critical to a system or organisation.

Verb

To adopt as, or serve as, a central cohesive source of stability and security.

Synonyms

lynchpin

mainstay

pin

backbone

keystone

anchor

⚓

cotter

dog

🐕

forelock

key factor

kingpin

leader

peg

pillar

shaft

axle-pin

swivel pin

axlebolt

coupling pin

base

bigwig

buttress

core

cornerstone

Pronounced as (IPA)

/ˈlɪnt͡ʃˌpɪn/

Etymology

Inherited from Middle English: lynspin

Cognate with German: Lünse

Cognate with Dutch: luns

Cognate with Welsh: olwyn

Cognate with Classical Armenian: ողն

Cognate with Sanskrit: आणि

In summary

From Middle English lynspin, compound of lins (“axletree”) and pin, from Old English lynis (“lynchpin”), from Proto-West Germanic *lunis, from Proto-Germanic *lunaz – compare German Lünse and Dutch luns – from Proto-Indo-European. Possible further cognates are Welsh olwyn (“wheel”), Old Armenian ողն (ołn, “back; spine, backbone”) and Sanskrit आणि (āṇí, “lynchpin”). Figurative use attested from the mid-20th century.