What is expressing, or consisting of, the number two; belonging to two; as, the dual number of nouns, etc. , in Greek. Here you have one half of our dual truth. Tyndall called?

dual — Expressing, or consisting of, the number two; belonging to two; as, the dual number of nouns, etc. , in Greek. Here you have one half of our dual truth. Tyndall. (Webster's 1913.)

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