underlying

American  

[uhn-der-lahy-ing] / ˈʌn dərˌlaɪ ɪŋ /

adjective

1. lying or situated beneath, as a substratum.

2. fundamental; basic.

   the underlying cause of their discontent.

3. implicit; discoverable only by close scrutiny or analysis.

   an underlying seriousness in his witticisms.

4. (of a claim, mortgage, etc.) taking precedence; anterior; prior.

5. Linguistics. belonging to an earlier stage in the transformational derivation of a sentence or other structure; belonging to the deep structure.

---

underlying British  

/ ˌʌndəˈlaɪɪŋ /

adjective

1. concealed but detectable

   underlying guilt

2. fundamental; basic

3. lying under

4. finance (of a claim, liability, etc) taking precedence; prior

---

Usage

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.

Etymology

Origin of underlying

First recorded in 1605–15; underlie + -ing ²

Example Sentences

Anthropic is racing to contain the fallout after accidentally exposing the underlying instructions it uses to direct Claude Code, the popular artificial-intelligence agent app that has won the company an edge with developers and businesses.

From The Wall Street Journal

The exposed code related to the tool's internal architecture but does not contain confidential data from Claude, the underlying AI model by Anthropic.

From Barron's

"The report shows that the rise in prices at the pump is far greater than that of underlying crude oil prices," Greenpeace said in a statement.

From Barron's

Furthermore, the underlying instruments on which ETFs are based are less liquid than the ETFs themselves.

From MarketWatch

A 54-person crew researched and managed the portfolio of 4,100 or so underlying loans.

From The Wall Street Journal

Related Words

• basic
• elemental
• hidden