cornerstone
- 01 B2 Upper Intermediate
the most important part of an idea, plan, or system that everything else is built on.
the fundamental or essential element upon which something is based or developed.
Simple“Trust is the cornerstone of any healthy relationship.”
In context“Free speech is often described as the cornerstone of a democratic society, providing the necessary framework for all other civil liberties to exist.”
“Soil carbon is a cornerstone of soil health, supporting nutrient cycling, biological activity, soil structure and the long-term functioning of soil ecosystems.”
“While talk of Rodri, a cornerstone of City’s success in recent seasons, potentially leaving the club has dominated the headlines, Maresca insisted his attention was on Sunday’s match rather than the transfer window.”
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.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.