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

The argillaceous slates or clayey slates make a smooth surface, but one which is easily destroyed when wet.

From The Future of Road-making in America by Hulbert, Archer Bulter

The material of the hill, however, is not the hard argillaceous sandstone of the lock site, but merely alluvial.

From The Panama Canal and its Makers by Cornish, Vaughan

In this process the free sulphuric acid formed by the oxidation of pyrites reacts upon the argillaceous material to form aluminium sulphate.

From De Re Metallica, Translated from the First Latin Edition of 1556 by Agricola, Georgius