underpinning

American  

[uhn-der-pin-ing] / ˈʌn dərˌpɪn ɪŋ /

noun

1. a system of supports beneath a wall or the like.

2. Often underpinnings. a foundation or basis.

   to uncover the emotional underpinnings of an illness.

3. Informal. underpinnings,

   1. underwear, especially women's underwear.

   2. the legs.

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underpinning British  

/ ˈʌndəˌpɪnɪŋ /

noun

1. a structure of masonry, concrete, etc, placed beneath a wall to provide support

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Etymology

Origin of underpinning

First recorded in 1480–90; under + pin + -ing ¹

Example Sentences

That is the same theory underpinning the controversial airstrikes since September on alleged drug traffickers' boats in the Caribbean and the Pacific.

From Barron's • May 29, 2026

The profits underpinning chip companies’ stocks are a distinction from the dot-com bubble, however, when many of the biggest winners had little or no earnings.

From The Wall Street Journal • May 28, 2026

The business logic underpinning all of it is a subscription model that distinguishes the Times sharply from traditional game companies.

From Barron's • May 16, 2026

Chongqing leads the country in car manufacturing, underpinning China's position as the world's largest car-maker.

From BBC • May 12, 2026

That is, to replace its interweaving but independent voices with a more unified, streamlined sound, with the keyboard and cello locked together supportively, underpinning the sparring interplay of the two violins above them.

From "The Story of Music" by Howard Goodall