underpinning

noun

un·​der·​pin·​ning ˈən-dər-ˌpi-niŋ 

1

: the material and construction (such as a foundation) used for support of a structure

2

: something that serves as a foundation : basis, support

—often used in plural

the philosophical underpinnings of educational methods

3

: underwear

—usually used in plural

4

: a person's legs

—usually used in plural

Synonyms

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

Examples of underpinning in a Sentence

the underpinnings of the theory have recently been called into question

the underpinnings of the bridge were seriously damaged in the collision

Recent Examples on the Web

Some 75 percent of the genes that cause genetic diseases in humans are also found in fruit flies, so understanding their neural underpinnings could shed light on our own. —Joe Spring, Smithsonian Magazine, 20 Dec. 2024

How To Clarify Higher Education's Message Messaging challenges may happen in part because many colleges have historically fallen back on their historic underpinnings as liberal arts institutions. —Brian Mitchell, Forbes, 17 Dec. 2024

As generative and other types of AI increasingly become organizational underpinnings, the conversation around who will own the various aspects of it may spark a new conversation around a company’s overall architecture. —Rachel Curry, CNBC, 12 Dec. 2024

Birthright citizenship’s legal underpinnings The notion of birthright citizenship can be traced to 1608 with Calvin’s Case, a British decision that became part of the common law adopted in the U.S. legal system’s early days. —Louis Jacobson, Austin American-Statesman, 12 Dec. 2024

Word History

First Known Use

15th century, in the meaning defined at sense 1

Kids Definition

underpinning

noun

un·​der·​pin·​ning ˈən-dər-ˌpin-iŋ 

1

: the foundation used for support of a structure

2

: prop entry 1, support

3

: a person's legs

—usually used in plural