bedrock

American  

[bed-rok] / ˈbɛdˌrɒk /

noun

1. Geology. unbroken solid rock, overlaid in most places by soil or rock fragments.

2. bottom layer; lowest stratum.

3. any firm foundation or basis.

   Technical courses will be founded on a bedrock of sound, general education so as to produce a well-rounded engineer.

4. the fundamental principles, as of a teaching, belief, or science.

   Let's strip away the cant and get down to bedrock.

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adjective

1. basic; fundamental.

bedrock British  

/ ˈbɛdˌrɒk /

noun

1. the solid unweathered rock that lies beneath the loose surface deposits of soil, alluvium, etc

2. basic principles or facts (esp in the phrase get down to bedrock )

3. the lowest point, level, or layer

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bedrock Scientific  

/ bĕd′rŏk′ /

1. The solid rock that lies beneath the soil and other loose material on the Earth's surface.

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Etymology

Origin of bedrock

An Americanism dating back to 1840–50; bed + rock ¹

Explanation

Bedrock is the hard layer of rock beneath looser rocks and soil. In some places, the bedrock is exposed, while in others it lies deep underground. A geologist who's interested in studying the bedrock in different areas might have to dig through the various layers of soil to reach that bedrock. You can also use the word in a figurative way, to mean "the heart of the matter," or "the basic, fundamental principles." For example, you might say that fairness and freedom is the bedrock of a good government. The word combines bed — here meaning "plot of land" — and rock.

Example Sentences

See Examples For:

bedrock

It was sparked by the partial collapse of a glacier and some of its bedrock.

From The Wall Street Journal ● Sep. 9, 2026

Preliminary investigations have pointed to a collapsed glacier and its bedrock as the cause of last week's flash flood.

From BBC ● Sep. 4, 2026

As government rates are the bedrock of capital costs throughout economies, the effects are far-reaching.

From MarketWatch ● Sep. 4, 2026

According to him, America would have burst into flames and melted into the bedrock mantle if he hadn’t come to town.

From Salon ● Aug. 21, 2026

This was the first manifestation of what I came to learn was bedrock Jesse ideology: He distrusted almost all authority and bureaucracy.

From "Geeks: How Two Lost Boys Rode the Internet Out of Idaho" by Jon Katz