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

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

Septarium, sep-tā′ri-um, n. an ovate flattened nodule of argillaceous limestone or ironstone—turtle-stone:—pl.

From Chambers's Twentieth Century Dictionary (part 4 of 4: S-Z and supplements) by Various

When much silica is diffused through the rock, we have a siliceous limestone; the presence of clay and of carbonaceous matter gives us argillaceous and carbonaceous limestones.

From Geology by Geikie, James