What is the definition of Mailing Blood Cells?

"Mailing blood cells" is a whimsical way of saying the act of sending out red and white blood cells, the unsung heroes of our circulatory system, like a postcard from your body's emergency room. Imagine this: "I sent my mailing blood cells to the moon to say, 'Dear Earth, I miss your... well, your lack of blood thinners.'"

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But let's switch gears to a darker example: "The hospital mailing blood cells to the rogue cult leader was as unorthodox as a vampire's secret recipe for eternal youth."