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

Political opinions become more certain than the underlying beliefs. — Literary Hub, 22 Sep. 2026

The category went viral on TikTok, though the underlying physiology predates the trend. — Hanna Wickes, Kansas City Star, 22 Sep. 2026

The partnership does not change that underlying extraction process. — Neetika Walter, Interesting Engineering, 22 Sep. 2026

Here, members of Forbes Technology Council identify recurring workplace tensions that leaders may be better able to address by fixing the underlying process. — Expert Panel®, Forbes.com, 21 Sep. 2026

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