Someone who you think is your friend but then totally backstabs you and leaves you alone.
“Wow she just like totally stole your boyfriend from you.”

“Omg it must be a beibhinn.”
by Sofieeeeeeeee November 2, 2019
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A debilitating disease where your breasts shrink and eventually fall off.
I lost my breasts to the beibhinn.
by ghale June 5, 2021
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