noun

basalt

BAS-olt

Basalt (noun) means a dark, dense volcanic rock formed when lava cools quickly; it makes up much of the ocean floor. Example: “The cliffs were made of black basalt columns formed by ancient lava flows.”

noun

A dark, dense volcanic rock formed when lava cools quickly; it makes up much of the ocean floor.

"The cliffs were made of black basalt columns formed by ancient lava flows."

"Basalt is one of the most common rock types on Earth."

How to use basalt

Learner’s notes

In plain EnglishA hard, dark rock that comes from cooled lava.

Common pairings

basalt columns basalt rock volcanic basalt

Word forms

basalts plural

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Fill the gap

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The cliffs were made of black _____ columns formed by ancient lava flows.

Etymology

From Latin basaltes, likely a scribal error for basanites, from Greek basanos, "touchstone" — itself borrowed from an Egyptian word for a hard stone.

Origin: Latin

Frequently asked questions

What does “basalt” mean?

The word “basalt” means a dark, dense volcanic rock formed when lava cools quickly; it makes up much of the ocean floor. In plain terms, a hard, dark rock that comes from cooled lava.

How do you pronounce “basalt”?

“Basalt” is pronounced BAS-olt (/bəˈsɔlt/ in IPA).

How do you use “basalt” in a sentence?

Here is “basalt” used in a sentence: “The cliffs were made of black basalt columns formed by ancient lava flows.”

What part of speech is “basalt”?

“Basalt” is a noun.

Where does the word “basalt” come from?

The word “basalt” comes from Latin. From Latin basaltes, likely a scribal error for basanites, from Greek basanos, "touchstone" — itself borrowed from an Egyptian word for a hard stone.