The Collaborative International Dictionary
Argillaceous \Ar`gil*la"ceous\, a. [L. argillaceus, fr. argilla.] Of the nature of clay; consisting of, or containing, argil or clay; clayey.
Argillaceous sandstone (Geol.), a sandstone containing much clay.
Argillaceous iron ore, the clay ironstone.
Argillaceous schist or state. See Argillite.
Wiktionary
a. pertaining to clay; made of, containing, or resembling clay
WordNet
adj. resembling or containing clay; "argillaceous rocks" [syn: clayey] [ant: arenaceous]
Wikipedia
Usage examples of "argillaceous".
Although the beaks and feet of birds are generally quite clean, I can show that earth sometimes adheres to them: in one instance I removed twenty-two grains of dry argillaceous earth from one foot of a partridge, and in this earth there was a pebble quite as large as the seed of a vetch.
Yet we should remember that the circumnutating sheathlike cotyledons of Phalaris, the hypocotyls of Solanum, and the epicotyls of Asparagus formed round themselves little circular cracks or furrows in a superficial layer of damp argillaceous sand.
Moreover, in several cases little open circular spaces or cracks in the argillaceous sand which surrounded the arched hypocotyls were visible, and these appeared to have been made by the hypocotyls having bent first to one and then to another side whilst growing upwards.
In order to learn whether the tentacles or glandbearing hairs circumnutate, the back of a young leaf, with the innermost tentacles as yet incurved, was firmly cemented with shellac to a flat stick driven into compact damp argillaceous sand.