What is relating to, or forming, the base. Basal cleavage. See under Cleavage. -- Basal plane (Crystallog.), one parallel to the lateral or horizontal axis called?

basal — Relating to, or forming, the base. Basal cleavage. See under Cleavage. -- Basal plane (Crystallog.), one parallel to the lateral or horizontal axis. (Webster's 1913.)

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