underpinning

1 of 2

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 plural

the philosophical underpinnings of educational methods

3

: underwear

—usually plural

4

: a person's legs

—usually plural

underpinning

2 of 2

present participle of underpin

Synonyms of underpinning

Noun

• basis
• foundation
• bedrock
• cornerstone

Examples of underpinning in a Sentence

Noun

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

Noun

The conversation and the word itself, which gives the seventh and final episode its title, unlocks the Biblical underpinnings and the complexities governing many of the main characters. — Daniel Fienberg, HollywoodReporter, 1 Oct. 2026

The phone, the radio, the television, the fax, the cell, texting, video calls, AI—who among us truly grasps its underpinnings? — Literary Hub, 28 Sep. 2026

The occasional hints on non-denim pieces come in the material’s colors for devoré tops, lace underpinnings and jacquard knits, which often reprise Dondup’s tribal logo. — Martino Carrera, Footwear News, 27 Sep. 2026

Underneath the bodywork are some relatively familiar underpinnings; Bentley shares technology with Porsche as both are part of the greater Volkswagen Group empire. — Jonathan M. Gitlin, ArsTechnica, 23 Sep. 2026

Word History

First Known Use

Noun

15th century, in the meaning defined at sense 1

Rhymes for underpinning

• beginning
• binning
• dinning
• ginning
• grinning
• inning
• pinning
• sinning
• skinning
• spinning
• thinning
• tinning

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