underlying

adjective

un·​der·​ly·​ing ˌən-dər-ˈlī-iŋ 

1

a

: lying beneath or below

the underlying rock is shale

b

: basic, fundamental

an investigation of the underlying issues

2

: evident only on close inspection : implicit

3

: anterior and prior in claim

underlying mortgage

4

: of or being present in deep structure

underlying word order

Synonyms

• abecedarian
• basal
• basic
• beginning
• elemental
• elementary
• essential
• fundamental
• introductory
• meat-and-potatoes
• rudimental
• rudimentary

Examples of underlying in a Sentence

the ocean and the underlying rock

the underlying differences between democracy and dictatorship

Recent Examples on the Web

Its underlying revenue rose 4.1%, driven by a 2.6% rise in volume and 1.6% pricing gains. —Trefis Team, Forbes, 20 Sep. 2024

The military responded by painting Arctic runways white to reflect the constant summer sunshine and keep the underlying permafrost cool—a potentially good idea grounded in physics that was stymied by the fact that the paint reduced the braking ability of planes. —Paul Bierman, Smithsonian Magazine, 19 Sep. 2024

Books With a new memoir 20 years after breakout hit ‘Leave (Get Out),’ JoJo is back in control Sept. 12, 2024 What are the challenges in presenting your characters’ points of view while also advancing the plot and underlying mystery? —Paula L. Woods, Los Angeles Times, 18 Sep. 2024

As well as some sugary snacks to soothe the underlying guilt that comes with sharing your children. —Jemima Kirke, Vogue, 17 Sep. 2024

Word History

First Known Use

1611, in the meaning defined at sense 1a

Kids Definition

underlying

adjective

un·​der·​ly·​ing ˌən-dər-ˌlī-iŋ 

1

: lying under or below

the underlying rock

2

: fundamental entry 1 sense 1

Medical Definition

underlying

adjective

un·​der·​ly·​ing -ˌlī-iŋ 

: serving as a basis or cause (as of secondary symptoms)

the underlying brain malformation that caused the hydrocephalus

—R. M. Henig