one in a thousand
Exceptionally uncommon, unique, or excellent. Hyphenated if used before a noun. This is a one-in-a-thousand opportunity for us—we'd be fools not to seize it while we have the chance! My grandmother really was one in a thousand, and we're all very blessed to have had her in our lives.
one in a thousand
and one in a hundred; one in a millionFig. nearly unique; one of a very few. He's a great guy. He's one in million. Mary's one in a hundred—such a hard worker.