from
The Collaborative International Dictionary of English v.0.48
Mettle \Met"tle\, 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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