foundation stone

American  

noun

1. any of the stones composing the foundation of a building.

2. a cornerstone.

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foundation stone British  

noun

1. a stone laid at a ceremony to mark the foundation of a new building

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Etymology

Origin of foundation stone

First recorded in 1645–55

Example Sentences

Watson’s 1965 textbook, “Molecular Biology of the Gene,” became a foundation stone of modern biology.

From Los Angeles Times

The burial of the time capsule was similar to a ceremony in 1872 during which the then Princess of Wales, Alexandra, laid a foundation stone at the hospital, also sealing a time capsule.

From BBC

Human oversight is a foundation stone of what is known as "responsible" AI.

From BBC

For example, Mali's junta leader Gen Assimi Goïta laid the foundation stone last month for a gold refinery, in which a Russian conglomerate, the Yadran Group, will have a minority stake.

From BBC

Community and musical kinship is Ezra Collective's foundation stone; one that can be traced back to the youth club Tomorrow's Warriors, where they first met in central London in 2012.

From BBC