1 noun person, group, etccrann seastacloch choirnéil c m uthe volunteers are the linchpin of their campaignis iad na daoine deonacha crann seasta a bhfeachtaisshe was the real linchpin of the partyba uirthise i ndáiríre a bhí seasamh an pháirtí2 noun event, law, idea, etcthis development is the linchpin of the projectis ar an bhforbairt seo atá an togra ag braththe jurisdiction question will be the linchpin in the casebeidh ceist na dlínse cinniúnach sa chás3 noun AUTO pin on axledealg acastórapionna rotha