un·der·lie | \ ˌən-dər-ˈlī \
underlay\ˌən-dər-ˈlā \; underlain\ˌən-dər-ˈlān \; underlying\ˌən-dər-ˈlī-iŋ \

Definition of underlie 

transitive verb

1 archaic : to be subject or amenable to

2 : to lie or be situated under

3 : to be at the basis of : form the foundation of : support ideas underlying the revolution

4 : to exist as a claim or security superior and prior to (another)

Examples of underlie in a Sentence

A tile floor underlies the rug. The river is underlain by limestone. We discussed the principles that underlay their methods. A theme of revenge underlies much of her writing.
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Recent Examples on the Web

But underlying this mountain of cheese is a tale of an already volatile agriculture industry in even more flux in the Trump era. Tara Golshan, Vox, "Why Trump’s trade agenda might worsen America’s cheese glut," 4 July 2018 Without independent verification, these claims should be taken with a pinch of salt, but the underlying technology is certainly solid. James Vincent, The Verge, "This Japanese AI security camera shows the future of surveillance will be automated," 26 June 2018 Just about all agree that underlying all this is a dysfunctional housing market. The Economist, "Giddy property prices are a test for Swedish policymakers," 21 June 2018 Even when the underlying technology was kept, the good-looking, easy-to-write application development that was promoted never really materialized. Peter Bright, Ars Technica, "From Win32 to Cocoa: A Windows user’s would-be conversion to Mac OS, part II," 27 May 2018 Of course, there are many engineering aspects of these bots—but underlying every bit of technological terror is some very fundamental physics. Rhett Allain, WIRED, "The Terrifying Technological Tactics Behind BattleBots," 27 Apr. 2018 But, mapping services are only as good as the underlying data, which can be expensive to acquire and maintain. Bill Gourgey, WIRED, "How Artificial Intelligence Could Prevent Natural Disasters," 10 July 2018 Despite the best efforts of the BEA’s excellent civil servants, the underlying data are noisy and incomplete, meaning that revisions to GDP growth estimates can be large and often confusing. Jason Furman, WSJ, "The Economy Is Growing Faster Than the Government Says," 9 July 2018 But in April, Pruitt moved to prevent the agency from considering studies where underlying data is private — like the Harvard one. Dino Grandoni, Washington Post, "The Energy 202: Supreme Court to rehear moose-hunting case with wider implications for Alaska," 19 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'underlie.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of underlie

before the 12th century, in the meaning defined at sense 1

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Statistics for underlie

Last Updated

22 Sep 2018

Look-up Popularity

Time Traveler for underlie

The first known use of underlie was before the 12th century

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More Definitions for underlie



English Language Learners Definition of underlie

: to lie or be located under (something)

: to form the basis or foundation of (an idea, a process, etc.)


un·der·lie | \ ˌən-dər-ˈlī \
underlay\-ˈlā \; underlain\-ˈlān \; underlying\-ˈlī-iŋ \

Kids Definition of underlie

1 : to lie or be located under A tile floor underlies the rug.

2 : to form the foundation of : support What ideals underlie democracy?

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Comments on underlie

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