1 definition by Ainz

Someone (or something) that has hidden exceptional characteristics and/or future potential, but currently lacks the final touches that would make them (or it) truly stand out from the crowd.

The phrase is metaphorical and relates to the fact that naturally occurring diamonds are quite ordinary at first glance, and that their true beauty as jewels is only realized through the cutting and polishing process.
She may seem shy and ordinary right now, but give her a couple more years - she truly is a diamond in the rough.
by Ainz January 24, 2006
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