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.

---

underpinning British  

/ ˈʌndəˌpɪnɪŋ /

noun

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

---

Etymology

Origin of underpinning

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

Example Sentences

Underpinning the deal was the plan to begin a long-term collaboration: The L.A.

From Los Angeles Times • Feb. 27, 2026

Underpinning their optimism is Goldman’s outlook for sturdy global economic growth with low inflation, easier monetary policy, and improved fiscal situations in some economies.

From Barron's • Jan. 26, 2026

Underpinning this existence is a deep reliance on the Kingdom of Denmark, of which Greenland is a semiautonomous territory.

From The Wall Street Journal • Jan. 15, 2026

Underpinning all their work is a humble nature.

From BBC • Oct. 22, 2025

Underpinning walls: To underpin the walls as specified, requiring 750 cubic feet of brick masonry, or less, amount of masonry not to exceed 750 cubic feet.

From The Repair Of Casa Grande Ruin, Arizona, in 1891 Fifteenth Annual Report of the Bureau of Ethnology to the Secretary of the Smithsonian Institution, 1893-94, Government Printing Office, Washington, 1897, pages 315-348 by Mindeleff, Cosmos