keystone

noun

key·​stone ˈkē-ˌstōn 

1

: the wedge-shaped piece at the crown of an arch that locks the other pieces in place see arch illustration

2

: something on which associated things depend for support

determination, a keystone of the puritan ethic

—L. S. Lewis

3

or keystone species : a species of plant or animal that produces a major impact (as by predation) on its ecosystem and is considered essential to maintaining optimum ecosystem function or structure

Synonyms

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

Examples of keystone in a Sentence

Tourism is the city's economic keystone.

the keystone of his faith

Recent Examples on the Web

A number of useful tools have been included to help take the sting out of setup, such as 1.3x zoom, auto vertical keystone plus manual horizontal, vertical lens shift, 8-point corner adjustment, and auto-fit to screen. —Paul Ridden, New Atlas, 2 Nov. 2024

This should be a warning flag for all because data analysis, be that software or hardware-related, is the keystone for most hacking activity. —Davey Winder, Forbes, 21 Oct. 2024

Optical zoom and vertical lens shift, along with autofocus, keystone correction, screen fit and obstacle avoidance, also help make positioning and setup a breeze. —New Atlas, 10 Oct. 2024

Catch up quick: The U.S. Supreme Court ruled in a bribery case involving a former Portage, Indiana, mayor that there is a difference between a bribe and a gratuity, essentially nixing a keystone corruption law for the federal government. —Justin Kaufmann, Axios, 9 July 2024

Word History

First Known Use

circa 1637, in the meaning defined at sense 1

Kids Definition

keystone

noun

key·​stone ˈkē-ˌstōn 

1

: the wedge-shaped piece at the top of an arch that locks the other pieces in place

2

: something on which other things depend