cornerstone
英検準1級礎・基礎
意味
- (建物の起工年月日を刻んだ)すみ石,定礎石
- 不可欠のもの;基礎,土台
語源
英語の原文（Wiktionary）
From Middle English corner ston; equivalent to corner + stone. The figurative sense is in part after Psalm 118:22, and is also quoted several times in the New Testament.