magma

noun

mag·​ma ˈmag-mə 

1

archaic : dregs, sediment

2

: a thin pasty suspension (as of a precipitate in water)

3

: molten rock material within the earth from which igneous rock results by cooling

magmatic

mag-ˈma-tik 

adjective

Examples of magma in a Sentence

Recent Examples on the Web

Granite Bowl — New Hampshire vs. Dartmouth Another state-specific bowl, but being known for a rock formed from volcanic magma is pretty cool. —Chris Vannini, New York Times, 8 July 2025

The team believes accessing such subterranean magma would take a similar approach to that of geothermal energy production — which harnesses heat from the Earth’s core and is a significant source of energy in Iceland. —Francesca Perry, CNN Money, 3 July 2025

Studying rocks from Earth’s earliest history could give a glimpse into how the planet may have looked — how its roiling magma oceans gave way to tectonic plates — and even how life got started. —Adithi Ramakrishnan, Los Angeles Times, 27 June 2025

Stealthy magma system behavior at Veniaminof Volcano, Alaska Rosie McCall is a freelance writer living in London. —Rosie McCall, Discover Magazine, 16 June 2025

Word History

Etymology

Middle English, from Latin magmat-, magma, from Greek, thick unguent, from massein to knead — more at mingle

First Known Use

15th century, in the meaning defined at sense 1

Kids Definition

magma

noun

mag·​ma ˈmag-mə 

: molten rock material within the earth

magmatic

mag-ˈmat-ik 

adjective

Medical Definition

magma

noun

mag·​ma ˈmag-mə 

1

: a crude mixture of mineral or organic matter in the state of a thin paste

2

: a suspension of a large amount of precipitated material (as in milk of magnesia) in a small volume of a watery vehicle