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

Novavax was approved for those 12 and older with an underlying condition and people over 65. —Mary Walrath-Holdridge, USA Today, 4 Sep. 2025

But the underlying tribal, religious, and political tensions have simmered for decades. —Charlie Campbell, Time, 4 Sep. 2025

Understanding the underlying forces reshaping the global order is no longer optional for corporate leaders. —Hbr Editors, Harvard Business Review, 4 Sep. 2025

Whatever the underlying motivation, the White House has been increasing pressure on Venezuela, including by putting a $50 million bounty on its leader last month. —Tasneem Nashrulla, semafor.com, 4 Sep. 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