mafic

adjective

maf·​ic ˈma-fik 

: of, relating to, or being a group of usually dark-colored minerals rich in magnesium and iron

Examples of mafic in a Sentence

Recent Examples on the Web

Its floor is nearly entirely covered in dark, mineral-rich rock — known as mafic material — containing magnesium, iron and minerals such as pyroxine and olivine. — Samantha Mathewson, Space.com, 6 Mar. 2026

Along the way, hikers are surrounded by mafic southern mixed chaparral, a unique type of chaparral vegetation that is found in mafic soils, which are rich in magnesium and iron. — Maura Fox, San Diego Union-Tribune, 6 Feb. 2026

The samples included mafic Archaean rocks derived from the Hadean–Eoarchaean mantle (including samples from Isua, Nuvvuagittuq, and the Kaapvaal Craton) and certain modern ocean island basalts (from La Réunion Island and Kama’ehuakanaloa volcano, Hawaii). — Pranjal Malewar, New Atlas, 3 Nov. 2025

The institution notes that Fuego's eruptions have become more mafic with time, meaning the volcano is expelling darker, denser lava with higher magnesium and iron content. — Josh Hammer, Newsweek, 19 Mar. 2025

However, there is a group of mafic eruptions that are high in magnesium and iron that also have that magnitude. — Smithsonian Magazine, 3 Jan. 2024

Basalt is also derived from melting the mantle, but in that case, only 10 to 20 percent is typically melting thanks to fractional melting (the lowest temperature minerals melt first, leaving behind the more mafic minerals/elements). — Erik Klemetti, Discover Magazine, 24 Oct. 2016

Word History

Etymology

New Latin magnesium + Latin ferrum iron + English -ic

First Known Use

1912, in the meaning defined above

Rhymes for mafic

• strophic
• catastrophic
• geostrophic
• philosophic
• pleomorphic
• ultramafic
• heterotrophic