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The step brother of your half sibling OR the half brother of your step sibling.
she married my unbrother, so I guess now she's my unsister-in-law
by ridl February 21, 2009
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2
The act of emotionally removing oneself from a sibling, specifically being a brother.
Lenny has been unbrothered.
by AGBBibag December 30, 2011
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