Exactly what it says. A balloon filled with blood.
Or, another word for blister, etc.
Little Jimmothy "MOM, I need a band-aid! I fell off my bike and now there's a blood balloon on my knee!"

Frequently asked questions:

"Are babies blood balloons?"

"Should i start stabbing babies with pins?"

The answer?
Yes.
by Apu Pibut July 1, 2011
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"I need to get more blood balloons because my period is starting."
by jolfstenberg October 15, 2015
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A dick. A dick is basically all blood.
I’m gonna give Cindy my blood balloon if she keeps wearing that dress
by PseudoNympho666 December 26, 2018
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