What does "shale" mean?

Shale: Etym: [G. shale.] (Geol.) A fine-grained sedimentary rock of a thin, laminated, and often friable, structure. Bituminous shale. See under Bituminous.

Additional senses

  1. 2.To take off the shell or coat of; to shell. Life, in its upper grades, was bursting its shell, or was shaling off its husk. I. Taylor.

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