# shale

/ˈʃeɪɫ/ (US) · /ʃˈeɪl/ (UK)

Source: https://englishreference.com/word/shale
Updated: 2026-06-20

## Senses

### 1. sedimentary rock

noun · CEFR C1 · Technical

a soft, dark rock that was formed from mud and can be split into thin, flat pieces.

For teachers: a fine-grained sedimentary rock formed by the compaction of silt and clay-size mineral particles; it is typically fissile, meaning it splits easily along laminations.

- The geologist found fossils of ancient leaves pressed between the layers of shale.
- The extraction of natural gas from deep shale formations has significantly altered the global energy landscape over the last decade.

Usage: Often used as an uncountable noun when referring to the material, but countable when referring to specific geological formations.

### 2. a shell or husk

noun · CEFR C2 · Archaic · Dialect

the outer shell or covering of a seed or fruit.

For teachers: the outer covering, husk, or pod of a plant or seed.

- He removed the dry shale from the grain before grinding it.
- In certain regional dialects, the term shale is still applied to the protective husks of legumes during the harvest season.

Teaching tip: This sense is extremely rare in modern English; learners will almost exclusively encounter the geological meaning.

### 3. to remove a shell

verb · CEFR C2 · Archaic

to take the outer skin or shell off something.

For teachers: to remove the shell, husk, or outer coating from a seed or fruit.

- The workers spent the afternoon shaling the peas for the evening meal.
- The traditional process involved shaling the nuts by hand before they were laid out to dry in the sun.

Usage: A transitive verb taking a direct object.

## Examples

- The hikers found pieces of dark shale along the river bank.
- Geologists examined the shale layers to determine the age of the fossils trapped inside the rock.
- The extraction of natural gas from deep shale formations has transformed the energy landscape, though the process remains controversial due to its significant environmental footprint.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.