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

Yet despite stronger earnings from oil and gas trading, BP reported weakness in some key financial underpinnings of those shareholder returns, even with Brent crude above $80 a barrel. —Bloomberg, Fortune Europe, 7 May 2024

Doctor Who is a show that’s more than capable of going dark and twisty and mythological, but the first two episodes have easily digestible hooks and — perhaps out of an over-abundance of caution — keep their thematic underpinnings muted. —Daniel Fienberg, The Hollywood Reporter, 3 Sep. 2019

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