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

According to research on the plates, parts of the rift are separating at a rate of .3 inches per year due to the movement of magma deep below the surface. —Katie Nadworny, Travel + Leisure, 14 May 2025

During Axial Seamount's last eruption in 2015, an enormous amount of magma poured out of the volcano, including one lava flow that was about 450 feet thick, according to researchers. —Denise Chow, NBC news, 8 May 2025

The implications were profound: With a lot of rocky material, tidal heating can make oceans of magma. —Robin George Andrews, Quanta Magazine, 25 Apr. 2025

An eruption is unlikely for now Typically, gases like water and carbon dioxide can separate and form bubbles during the rise and decompression of magma. —Mary Walrath-Holdridge, USA Today, 25 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