Shale (?), n. [AS. scealy, scalu. See Scalme, and cf. Shell.] 1. A shell or husk; a cod or pod. “The green shales of a bean.” Chapman.
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2. [G. shale.] (Geol.) A fine-grained sedimentary rock of a thin, laminated, and often friable, structure.
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Bituminous shale. See under Bituminous.
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