diabase

American  

[dahy-uh-beys] / ˈdaɪ əˌbeɪs /

noun

Petrology.

1. a fine-grained gabbro occurring as minor intrusions.

2. British. a dark igneous rock consisting essentially of augite and feldspar; an altered dolerite.

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diabase British  

/ ˈdaɪəˌbeɪs /

noun

1. an altered dolerite

2. another name for dolerite

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diabase Scientific  

/ dī′ə-bās′ /

1. A dark-gray to black, medium-grained igneous rock consisting mainly of labradorite and pyroxene. Diabase is compositionally similar to andesite, but has coarser grains. It is commonly found in sills and dikes.

2. Also called dolerite

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Other Word Forms

Derived Forms

• diabasic
  adjective

Etymology

Origin of diabase

1810–20; < French, equivalent to dia- (error for di- two) + base base ¹

Example Sentences

Diabase, dī′a-bās, n. a compact igneous rock, an altered form of basalt—included under the popular names greenstone and trap.—adj.

From Chambers's Twentieth Century Dictionary (part 1 of 4: A-D) by Various

Diabase, originally an equivalent of diorite; then used for chloritic igneous rocks of the Intermediate series of various grain; and now usually for a type of dolerite in which the felspar is embedded in augite.

From The New Gresham Encyclopedia Volume 4, Part 1: Deposition to Eberswalde by Various