[ uhn-der-lahy-ing ]
/ ˈʌn dərˌlaɪ ɪŋ /
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lying or situated beneath, as a substratum.
fundamental; basic: the underlying cause of their discontent.
implicit; discoverable only by close scrutiny or analysis: an underlying seriousness in his witticisms.
(of a claim, mortgage, etc.) taking precedence; anterior; prior.
Linguistics. belonging to an earlier stage in the transformational derivation of a sentence or other structure; belonging to the deep structure.



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“Was” is used for the indicative past tense of “to be,” and “were” is only used for the subjunctive past tense.

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Origin of underlying

First recorded in 1605–15; underlie + -ing2
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021


What does underlying mean?

Underlying most literally means situated underneath—lying under something, as in We have to fix the underlying layer before repairing the surface.

Underlying perhaps most commonly means fundamental or basic. This sense of the word is used to describe things that are the basis, foundation, or cause of something else. A person’s underlying beliefs are their most essential beliefs, the ones that all their other beliefs, opinions, or values are based on. A single, underlying issue may be the basis of many other problems. Symptoms are caused by an underlying condition or disease.

Less commonly, underlying can be used to describe something that lies beneath in a figurative way, especially something that’s difficult to detect because it’s partially hidden, such as underlying guilt or the underlying theme of a poem.

Underlying is also the continuous tense (ing– form) of the verb underlie, meaning to literally lie beneath or to be the basis or foundation of, as in This is the main problem that underlies all the other issues. 

In a financial context, underlying is used more narrowly as a way of indicating what came first or what has precedence, such as in things like mortgages or insurance claims.

Example: We are still working to determine the underlying cause of the collapse.

Where does underlying come from?

The first records of the word underlying come from the early 1600s. It comes from the verb underlie, which is recorded much earlier, before 900. The word lie is used in the sense of “to be situated.”

Underlying is perhaps most often used to describe things that are situated at the figurative foundation or root of other things. This sense of the word can be used quite broadly. A thing described as underlying may form the basis of something, it may be the cause of something, or it may be the core motivation for something.

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What are some synonyms for underlying?

What are some words that share a root or word element with underlying

What are some words that often get used in discussing underlying?

How is underlying used in real life?

Underlying can be used both literally and figuratively. It’s used in many different contexts.



Try using underlying!

Which of the following words is NOT a synonym of underlying?

A. basic
B. root
C. surface
D. foundational

Example sentences from the Web for underlying

British Dictionary definitions for underlying

/ (ˌʌndəˈlaɪɪŋ) /


concealed but detectableunderlying guilt
fundamental; basic
lying under
finance (of a claim, liability, etc) taking precedence; prior
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012