underlying

adjective

un·​der·​ly·​ing ˌən-dər-ˈlī-iŋ How to pronounce underlying (audio)
Synonyms of underlying
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 of underlying

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Examples of underlying in a Sentence

the ocean and the underlying rock the underlying differences between democracy and dictatorship
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
If hearths had been built in the cave, underlying bones would have shown evidence of charring — but not a single bone out of the 4,500 studied was burned. — Ashley Strickland, CNN Money, 3 July 2026 The question is whether to address the underlying source of the gap that CDI tools and coding software exist to manage. — Mike Valli, Forbes.com, 8 July 2026 This is a clear example of how technology enables equipment upgrades without needing to rip and replace the underlying hardware asset. — Amit Chaturvedy, Fortune, 8 July 2026 With that, several underlying issues also arise, such as unpredictable power spikes that threaten to destabilize voltage levels. — Mrigakshi Dixit, Interesting Engineering, 6 July 2026 See All Example Sentences for underlying

Word History

First Known Use

1611, in the meaning defined at sense 1a

Time Traveler
The first known use of underlying was in 1611

Rhymes for underlying

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Browse Nearby Words

underly
underlying
underlying bond
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Cite this Entry

“Underlying.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/underlying. Accessed 10 Jul. 2026.

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Kids Definition

underlying

adjective
un·​der·​ly·​ing ˌən-dər-ˌlī-iŋ How to pronounce underlying (audio)
1
: lying under or below
the underlying rock
2
: fundamental entry 1 sense 1

Medical Definition

underlying

adjective
un·​der·​ly·​ing -ˌlī-iŋ How to pronounce underlying (audio)
: serving as a basis or cause (as of secondary symptoms)
the underlying brain malformation that caused the hydrocephalus—R. M. Henig

More from Merriam-Webster on underlying

Nglish: Translation of underlying for Spanish Speakers

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