argillaceous

American  

[ahr-juh-ley-shuhs] / ˌɑr dʒəˈleɪ ʃəs /

adjective

1. Geology, Petrology. of the nature of or resembling clay; clayey.

2. containing a considerable amount of clayey matter.

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argillaceous British  

/ ˌɑːdʒɪˈleɪʃəs /

adjective

1. (of sedimentary rocks and deposits) composed of very fine-grained material, such as clay, shale, etc Compare arenaceous rudaceous

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Etymology

Origin of argillaceous

First recorded in 1725–35, argillaceous is from the Latin word argillāceus clayish. See argil, -aceous

Example Sentences

Geologist Paula Messina showed that the ground is covered by argillaceous sediments and bacterial mats, forming under wet conditions a very slippery surface.

From Scientific American • Jul. 22, 2013

The girls ticked off aquarellist, staphylococcic, gracilescent, adscititious, eupraxia, argillaceous, autochthan and umbelliferous.

From Time Magazine Archive

Laterite, lat′ėr-īt, n. an argillaceous sandstone of a reddish or brick colour found in India, esp. in Ceylon.

From Chambers's Twentieth Century Dictionary (part 2 of 4: E-M) by Various

In places where Algæ do not generate peat, they may nevertheless leave traces of their form imprinted on argillaceous and calcareous mud, as they are usually very tough in their texture.

From Principles of Geology or, The Modern Changes of the Earth and its Inhabitants Considered as Illustrative of Geology by Lyell, Charles, Sir

Secondly, the inlet grew shallower, and the water became brackish, or alternately salt and fresh, so that the remains of freshwater and marine shells were mingled in the blue argillaceous sediment of its bottom.

From Principles of Geology or, The Modern Changes of the Earth and its Inhabitants Considered as Illustrative of Geology by Lyell, Charles, Sir