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

Cleavage.—Fine-grained rocks, more especially those which are argillaceous, occasionally shew another kind of structure, which is called cleavage.

From Geology by Geikie, James

Some were partially painted with a white argillaceous earth; others were blackened with charcoal; one of the men was daubed all over with a white pigment.

From Narrative of the surveying voyages of His Majesty's ships Adventure and Beagle, between the years 1826 and 1836 Volume I. - Proceedings of the First Expedition, 1826-1830 by Fitzroy, Robert

The south-eastern end of the dam abuts on the hill of hard, fine-grained, argillaceous sandstone in which the lock-site is being excavated.

From The Panama Canal and its Makers by Cornish, Vaughan