Mettle (?), n. [E. metal, used in a tropical sense in allusion to the temper of the metal of a sword blade. See Metal.] Substance or quality of temperament; spirit, esp. as regards honor, courage, fortitude, ardor, etc.; disposition; -- usually in a good sense; as, to test a person's mettle.
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A certain critical hour which shall . . . try what mettle his heart is made of. South.
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Gentlemen of brave mettle. Shak.
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The winged courser, like a generous horse,
Shows most true mettle when you check his course. Pope.
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To put one one's mettle, to cause or incite one to use one's best efforts.
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