cornerstone

noun

cor·​ner·​stone ˈkȯr-nər-ˌstōn 

1

: a stone forming a part of a corner or angle in a wall

specifically : such a stone laid at a formal ceremony

2

: a basic element : foundation

a cornerstone of foreign policy

Synonyms

• base
• basis
• bedrock
• bottom
• footing
• foundation
• ground
• groundwork
• keystone
• root
• underpinning
• warp
• warp and woof

Examples of cornerstone in a Sentence

Officials held a ceremony to lay the cornerstone for a new library.

Trust is the cornerstone of their relationship.

Recent Examples on the Web

With Ogwumike, the No. 1 selection in the 2012 draft, joining the Seattle Storm in free agency, the Sparks are in need of a franchise cornerstone to galvanize the organization that is in danger of getting left behind in the evolving league. —Thuc Nhi Nguyen, Los Angeles Times, 13 Apr. 2024

The event spinoff pic is a cornerstone of Paramount’s slate, and hopes to be another win for the innovative horror franchise created by John Krasinski that turned into a major hit after successfully proving that original stories can work on a large, commercial scale. —Pamela McClintock, The Hollywood Reporter, 11 Apr. 2024

Word History

First Known Use

13th century, in the meaning defined at sense 1

Kids Definition

cornerstone

noun

cor·​ner·​stone ˈkȯr-nər-ˌstōn 

1

: a stone forming part of a corner in a wall

2

: something of basic importance

the cornerstone of our foreign policy