underpin

American  

[uhn-der-pin] / ˌʌn dərˈpɪn /

verb (used with object)

• underpins,
  present (3rd person singular)
• underpinned,
  past participle,  past
• underpinning
  present participle

1. to prop up or support from below; strengthen, as by reinforcing a foundation.

2. to replace or strengthen the foundation of (a building or the like).

3. to furnish a foundation for; corroborate.

   The author's conclusions are underpinned by references to experimental findings.

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underpin British  

/ ˌʌndəˈpɪn /

verb

1. to support from beneath, esp by a prop, while avoiding damaging or weakening the superstructure

   to underpin a wall

2. to give corroboration, strength, or support to

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Other Word Forms

Inflected Forms

Participles

• underpinning
  present
• underpinned
  past

Conjugated Forms

Present

• underpin
  simple
• underpins
  simple
• have underpinned
  perfect
• has underpinned
  perfect
• am underpinning
  progressive
• are underpinning
  progressive
• is underpinning
  progressive
• have been underpinning
  perfect progressive
• has been underpinning
  perfect progressive

Past

• underpinned
  simple
• had underpinned
  perfect
• was underpinning
  progressive
• were underpinning
  progressive
• had been underpinning
  perfect progressive

Future

• will underpin
  simple
• will have underpinned
  perfect
• will be underpinning
  progressive
• will have been underpinning
  perfect progressive

Etymology

Origin of underpin

First recorded in 1515–25; under- + pin

Explanation

To underpin is to justify or support the ideas behind something, the way your extensive research underpins your self-published book on ice cream trucks in the United States. Whenever you substantiate someone's claims, theories, or stories, you underpin them. A slightly different way to underpin is to form the basis or foundation of something: "A philosophy of empathy and kindness underpins all the interactions at my wonderful summer camp." This verb can also be used in a more literal way, to mean "support from below," the way the foundation of a house underpins everything that's built on top of it.

Example Sentences

See Examples For:

underpin underpins underpinned underpinning

He tells clients in a note that operating leverage across asset management and personal banking should underpin mid-to-high single-digit earnings growth into fiscal 2029.

From The Wall Street Journal ● Sep. 28, 2026

A lack of distributions and write-offs reduces available funds that underpin economic activity, creating adverse feedback loops.

From MarketWatch ● Sep. 23, 2026

The UK government said the new space strategy would "drive growth, strengthen security and back the technologies that underpin modern life".

From BBC ● Sep. 8, 2026

But when these topics underpin a massive, sold-out festival of music with an audience of young women, it becomes “part of ordinary civic life,” she said.

From Los Angeles Times ● Aug. 27, 2026

The AIG FP traders present were shocked by how little thought or analysis seemed to underpin the subprime mortgage machine: It was simply a bet that home prices would never fall.

From "The Big Short" by Michael Lewis

"By combining complementary X-ray techniques at LCLS, this work provides a uniquely complete view of these coupled processes, opening new opportunities to understand and ultimately control the chemistry that underpins energy conversion and catalysis."

From Science Daily ● Oct. 6, 2026

Rombach, 33, helped develop latent diffusion, a breakthrough that underpins many of today's AI image-generation systems.

From Barron's ● Sep. 27, 2026

Domestic production of primary aluminum provides the foundational metal needed to produce the military-grade aluminum that underpins mission-critical weapons systems and defense equipment.

From The Wall Street Journal ● Sep. 13, 2026

It estimates that Himalayan water underpins roughly 20% of India's GDP, sustaining wheat, rice, tea, hydropower and pilgrimage economies.

From BBC ● Sep. 13, 2026

When the experimental method is successful in explaining what was previously inexplicable, it thus not only establishes particular scientific theories, it also confirms the validity of the general approach which underpins experimentation.

From "The Invention of Science" by David Wootton

Based in a city of more than half a million people, their potential is underpinned by a large, passionate fanbase who averaged over 30,000 for home games in the second tier last term.

From BBC ● Oct. 10, 2026

A major reason homeownership underpinned wealth for previous generations is that a mortgage can function as a sort of forced savings account.

From MarketWatch ● Sep. 16, 2026

That end-of-era feeling underpinned the Bandung conference, held on the Indonesian island of Java in the spring of 1955.

From The Wall Street Journal ● Sep. 11, 2026

Treasury Secretary Scott Bessent have underpinned the recovery.

From The Wall Street Journal ● Sep. 10, 2026

It simply interested him—greatly—how all the cultures of Zeru were underpinned by the same story.

From "Strange the Dreamer" by Laini Taylor

Bovine and ovine meat prices were broadly stable, with stronger U.S. demand supporting Brazilian beef prices and firm global demand underpinning sheep meat prices in Oceania.

From The Wall Street Journal ● Oct. 2, 2026

The basic logic underpinning his thinking is that the more people who own and use bitcoin, the greater the adoption of its network, which can provide a base for assessing its value.

From MarketWatch ● Sep. 28, 2026

Yet, the technology underpinning autonomous warfare risks outpacing the Russian and Ukrainian frameworks for maintaining some degree of human control over weapons.

From Salon ● Sep. 24, 2026

The AI product space is increasingly competitive, underpinning demand for computing power and AI infrastructure, the strategists add.

From The Wall Street Journal ● Sep. 23, 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