underlie

verb

un·​der·​lie ˌən-dər-ˈlī 

underlay ˌən-dər-ˈlā  ; underlain ˌən-dər-ˈlān  ; underlying ˌən-dər-ˈlī-iŋ 

transitive verb

1

: to lie or be situated under

2

: to be at the basis of : form the foundation of : support

ideas underlying the revolution

3

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

4

archaic : to be subject or amenable to

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.

Recent Examples on the Web

That’s where a CEF’s discount to net asset value (NAV, or the value of the fund’s underlying portfolio) is still wide but is slowly moving toward par. —Michael Foster, Forbes.com, 29 Mar. 2025

Forty cases have been hospitalized, and one death has been reported—a 6-year-old unvaccinated girl who had no underlying health conditions. —Eric Berger, ArsTechnica, 26 Mar. 2025

As well as Fitzgerald played, his underlying data paints a bleaker picture. —Justice Delos Santos, Mercury News, 26 Mar. 2025

And through it all, Quy’s love for rural Vietnam underlies every frame, every movement, like the love that vibrates between Việt and Nam deep underground. —David Opie, IndieWire, 26 Mar. 2025

Word History

First Known Use

before the 12th century, in the meaning defined at sense 4

Rhymes for underlie

• apply
• awry
• belie
• bely
• bigeye
• bonsai
• buckeye
• comply
• coxae
• decry
• defy
• deny

Kids Definition

underlie

verb

un·​der·​lie ˌən-dər-ˈlī 

underlay -ˈlā  ; underlain -ˈlān  ; underlying -ˈlī-iŋ 

1

: to lie or be located under

2

: to form the foundation of : support

ideas underlying the revolt