What is the definition of Undefined Blood Cells?

"Undefined blood cells" is like a mystery in the medical world - it's a medical jabber-mast about cells that don't quite fit into our blood cell family tree, but don't worry, it's not super scary. They're like the bad guys in a blood cell superhero movie who just can't find their spots and are, well, undefined.

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Now, here's a sentinel sentence for your taste: "The detective of the human body, solving the 'Undefined Blood Cells' case, found them in the old, forgotten library of the spleen - a place where the blood cells get to sleep and wonder why they're not just running faster."