Shale

How to spell shale

5 letters · 1 syllable

How to pronounce shale

What does shale mean?

1. nounA fine-grained sedimentary rock formed from compacted mud or clay that splits easily into thin layers.

Shale in a sentence

• The cliff was made of soft grey shale that crumbled underfoot.

• The company drilled deep to extract gas trapped in the shale.

Where does shale come from?

Language of origin: Germanic

Shale comes from the Old English word scealu, which meant a shell or a husk, the thin outer covering that flakes away from a seed or a nut. That noun belongs to the same Germanic family as the modern words shell and scale, and a close relative survives in the German Schale, meaning shell, peel, or rind. The link is the idea of a thin, splitting layer, and that is exactly the defining feature of the rock: shale is a fine-grained sedimentary stone that flakes apart into flat sheets. The geological sense became established in English during the eighteenth century, reinforced by the related German mining term Schiefer for similar layered rock. Because the word is so short and follows the plain English -ale pattern seen in pale, tale, and stale, the spelling is largely phonetic and gives few surprises.

How the word is built

• shale (a single Germanic root meaning shell or scale, applied to a rock that splits into flat layers)