礎石|そせきsoseki[0]heiban (flat)

1. nounfoundation stone; cornerstone

• Synonym土台どだいNeutralThe everyday word for a foundation or base; plainer than 「礎石」, and also used adverbially to mean 'fundamentally'.
• Synonym礎いしずえWrittenThe native Japanese counterpart of 「礎石」; written in tone, mostly figurative for the foundation of a nation or enterprise.
• Synonym基底きていWrittenA written-style term for a foundation lying one level deeper; also the mathematical term 'basis'.
• Synonym基盤きばんNeutralPoints to the infrastructure or framework that supports a whole, such as a nation's economic or industrial underpinnings.
• Related基礎きそNeutralThe most common everyday word for foundation; covers both building foundations and the essential part of something.
• Related根底こんていWrittenA written-style word for the very root of something, its deepest level; see 「根底から覆す」, overturn from the ground up.
• Related根拠こんきょNeutralPoints to grounds or justification — the reason something holds; not a physical cornerstone, so it cannot stand in for 「礎石」 in that sense.
• RelatedベースNeutralA loanword for base; colloquial in feel, and also names a baseball base — a sense far removed from 「礎石」.

Use 「礎石」 for the stone a building's structure rests on or, figuratively, the basis of an enterprise, as in 「礎石を築く」; the native word is 「礎」; for everyday 'foundation' pick 「基礎」 or 「土台」.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 建造物けんぞうぶつの基礎きそとなる石いし。
2. 物事ものごとの基礎きそ、土台どだいとなるもの。