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prove one's mettle

idiom

: to prove how tough one is
He proved his mettle as a fighter tonight.

Browse Nearby Words

prove one's manhood
prove one's mettle
prove oneself
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“Prove one's mettle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/prove%20one%27s%20mettle. Accessed 29 Nov. 2025.

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