gabbro

American  

[gab-roh] / ˈgæb roʊ /

noun

Petrology.

plural

gabbros

1. a dark granular igneous rock composed essentially of labradorite and augite.

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gabbro British  

/ ˈɡæbrəʊ /

noun

1. a dark coarse-grained basic plutonic igneous rock consisting of plagioclase feldspar, pyroxene, and often olivine

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gabbro Scientific  

/ găb′rō /

1. A usually dark, coarse-grained igneous rock composed mostly of plagioclase feldspar and clinopyroxene, and sometimes olivine. Gabbro is the coarse-grained equivalent of basalt.

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Other Word Forms

• gabbroic adjective
• gabbroid adjective
• gabbroitic adjective

Etymology

Origin of gabbro

< Italian; akin to Latin glaber smooth

Compare meaning

How does gabbro compare to similar and commonly confused words? Explore the most common comparisons:

• gabbro vs. basalt

Example Sentences

Prior research shows that some forms of metals production from gabbro and similar rocks aren’t commercially feasible—they can be costly because of more complex and energy-intensive processes that produce a lot of waste.

From The Wall Street Journal • Dec. 10, 2025

"These elements allowed us to look back through the chemical changes that TTG magmas go through and trace the melt compositions back to their initial state and source -- most likely a sort of gabbro."

From Science Daily • Jan. 31, 2024

In retrospect, it is clearer now that the gabbro was never going to get along with the coring drill.

From Scientific American • Aug. 12, 2021

These dark ferromagnesian minerals are commonly found in gabbro, basalt, diorite, and often form the black specks in granite.

From Textbooks • Jan. 1, 2017

The granite is not the oldest of the Cornish rocks; these are found in the Lizard peninsula and are represented by serpentine, gabbro and metamorphic schists.

From Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 4 "Coquelin" to "Costume" by Various