foliation

American  

[foh-lee-ey-shuhn] / ˌfoʊ liˈeɪ ʃən /

noun

1. the act or process of putting forth leaves.

2. the state of being in leaf.

3. Botany.

   1. the arrangement of leaves within a bud.

   2. the arrangement of leaves on a plant.

4. leaves or foliage.

5. Printing. the consecutive numbering of the folios or leaves, as distinguished from pages, of a manuscript or book.

6. the total number of such leaves.

7. Petrology. a form of lamination produced in rocks by metamorphism.

8. ornamentation with foliage, or an arrangement of foliage.

9. Architecture.

   1. ornamentation with foils.

   2. ornamentation with representations of foliage.

10. formation into thin sheets.

11. the application of foil to glass to make a mirror.

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foliation British  

/ ˌfəʊlɪˈeɪʃən /

noun

1. botany

   1. the process of producing leaves

   2. the state of being in leaf

   3. the arrangement of leaves in a leaf bud; vernation

2. architect

   1. ornamentation consisting of foliage

   2. ornamentation consisting of cusps and foils

3. any decoration with foliage

4. the consecutive numbering of the leaves of a book

5. geology the arrangement of the constituents of a rock in leaflike layers, as in schists

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foliation Scientific  

/ fō′lē-ā′shən /

1. The set of layers visible in many metamorphic rocks as a result of the flattening and stretching of mineral grains during metamorphism.

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Other Word Forms

• subfoliation
  noun
• superfoliation
  noun

Etymology

Origin of foliation

First recorded in 1615–25; foliate + -ion

Example Sentences

In fact, original sedimentary layering may be partially or completely obscured by the foliation.

From Textbooks • Jan. 1, 2017

Slate is a fine-grained metamorphic rock that exhibits a foliation called slaty cleavage that is the flat orientation of the small platy crystals of mica and chlorite forming perpendicular to the direction of stress.

From Textbooks • Jan. 1, 2017

Thumbnail: Folded foliation in a metamorphic rock from near Geirangerfjord, Norway.

From Textbooks • Jan. 1, 2017

In a manner like the Gros Ventre slide, foliation planes of weakness in metamorphic rock outcrops were parallel with the surface, compromising shear strength.

From Textbooks • Jan. 1, 2017

There have also been, of course, earth movements acting on the solid rock at a later time and injection of dikes both parallel to and across the primary foliation.

From Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 8 "Chariot" to "Chatelaine" by Various