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

The new study doesn’t rule out a far deeper magma ocean. —Robin Andrews, Wired News, 15 June 2025

Hydrothermal explosions occur when water underground is rapidly heated by a geothermal source, such as magma. —Owen Clarke, Outside Online, 6 June 2025

Those samples can be compared with the PKT region moon rocks to provide snapshots of the lunar mantle during two different eras, which, in turn, can help determine when the lunar magma ocean formed. —Nola Taylor Tillman, Space.com, 5 May 2025

The magma reservoir, where gases and liquids seemed to accumulate, was directly under the center of the volcano. —Monica Cull, Discover Magazine, 28 Apr. 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