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

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

The clay appears to have originated from the decomposition of shale; for it may be observed in all stages of the decomposition, from a well-characterized argillaceous slate, to plastic clay.

From Scenes and Andventures in the Semi-Alpine Region of the Ozark Mountains of Missouri and Arkansas by Schoolcraft, Henry Rowe

The cementing material may be siliceous or argillaceous, and is sometimes calcareous.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 5 "Greek Law" to "Ground-Squirrel" by Various