BiochemDude's definitions
The practice of substituting one's friends for their own genetic siblings. May be due to geographic or emotional separation. Sometimes this practice is colloquialized as a brother from another mother BFAM.
Steve's brother couldn't make it to the game, so he made a last minute sibstitution with his friend Mike. Stacy sibstituted her friend Becca, because her sister lived 12 hours away.
by BiochemDude June 14, 2016
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